Industry Medicine Research integrity

Facts and Fiction of Cassava Sciences

Attack is the best form of defence. Especially when your commercial clinical research is tainted by preclinical Photoshop fraud.

A novel Alzheimer’s drug is being tested in clinical trials in USA. The US company Cassava Sciences is ready to earn billions of dollars, convinced to have the game-changer, verified in the lab and in soon in clinic. And then concerns are publicly raised with FDA about falsified preclinical research data with that same drug, funded by that same company, done in the New York lab of their long-term board member, Hoau-Yan Wang. Cassava retaliated with a full–blown attack on its critics via a press release. Which provoked Elisabeth Bik to have a look as well.

On 23 August 2021, the US medical regulatory authority FDA posted this document, a kind of “Citizen’s Petition” by a law firm addressed to the FDA:

Statement of Concern Regarding the Accuracy and Integrity of Clinical and Preclinical Data Supporting the Ongoing Clinical Evaluation of Compound PTI-125, Also Known As Simufilam re Citizen Petition from Labaton Sucharow

This happens when concerned investors employ a law firm to investigate the evidence of research misconduct and get their money back from the accused company. For example, something like this is currently happening to Athira Pharma:

Here, it is about the company Cassava Sciences, founded by its CEO Remi Barbier. The law firm Labaton Sucharow acted apparently on some internal whistleblower information, because there was no PubPeer evidence at that time, and engaged a scientific image integrity expert to verify and summarise the concerns. Part A of the lawyers’ report is an Executive Summary:

“For over 15 years, Cassava Sciences (previously Pain Therapeutics, Inc, PTI) has funded the lab of Dr. Hoau-Yan Wang at City University of New York (CUNY). Together with Dr. Lindsay Burns at Cassava, Dr. Wang has published nearly a dozen papers connecting Filamin A protein with pain and Alzheimer’s disease (AD).
Cassava Sciences created a drug candidate called simufilam (previously PTI-125) that they claim binds Filamin A and has beneficial effects in biochemical and animal models of AD. The studies from Drs. Wang and Burns discussed in this dossier were used by Cassava Sciences to garner NIH grants and to open an investigational new drug (IND) application to study simufilam in AD patients. They form the basic science foundation for two completed clinical trials (phase IIa and IIb) which exposed over 70 patients to simufilam. Cassava Sciences is
currently recruiting 200 additional patients for a follow-up open-label trial.
This report raises concerns about the quality and integrity of the laboratory-based studies surrounding this drug candidate.

To preface the analysis that follows, no other labs have confirmed this research connecting Filamin A to pain or AD. No other labs have confirmed that simufilam binds or modifies Filamin A or has effects in AD models.”

In Part B, the lawyers explain that their sources are public (i.e., published research papers) and that

This letter details a long-standing pattern of seemingly intentional data manipulation and misrepresentation in scientific papers and corporate disclosures authored primarily by Drs. Hoau-Yan Wang, Associate Medical Professor, City University of New York, and Lindsay A Burns, Sr. Vice President of Neuroscience at Cassava Sciences.

Hoau-Yan Wang is member of Cassava’s advisory board, according to the lawyers for over 15 years already.

What follows soon after, is Part C, where evidence of research fraud is presented. Mostly, it’s about falsified western blots. This was the first criticised paper:

H.-Y. Wang, E. Friedman, M.C. Olmstead, L.H. Burns Ultra-low-dose naloxone suppresses opioid tolerance, dependence and associated changes in mu opioid receptor-G protein coupling and Gbetagamma signaling Neuroscience (2005) doi: 10.1016/j.neuroscience.2005.06.003 

Labaton Sucharow letter: “The western blot in Figure 1a (below right) of Dr. Wang’s 2010 paper in Biological
Psychiatry 67:522 contains four bands that closely resemble an image published in Figure 12a
(left) of the Wang and Burns 2005 Neuroscience 135: 247 paper

Cassava immediately issued a rebuttal to the Labaton Sucharow accusations via a press release, point-by-point retorting to “Fiction” with “Fact”. To me it would kind of make sense actually, if one swaps the Fiction and Fact labels. For example, regarding the western blots like the above, Cassava declared:

Bik: “the left most Actin lane in “Striatum” section of Figure 12A of this paper looks remarkably similar to the second-from-the-left Actin lane in the “Spinal Cord” section.”

Fiction: Western blots data are identical, more evidence of image manipulation.
Fact: The Western blots bands shown in the allegation are control bands. Control bands are supposed to be highly similar (since they show equal amounts of protein between lanes). Bands show clear differences when expanded. In addition, image manipulation of control bands makes no sense since these would not change the end data.

Well, that is an old and tired “it’s just controls excuse”. Without controls, a scientific experiment (or a clinical trial) becomes largely meaningless. Imagine Cassava would sell a weight loss supplement instead of an Alzheimer drug. Their advertisement shows a Before and After photos, on the right a lean muscular man, on the left the same picture of same man just photoshopped to make him look fat. What? You aren’t interested in the supplement anymore? It’s just controls! The two men are supposed to be highly similar! Look, the fat guy shows clear differences when expanded. And anyway, manipulation of control male models makes no sense since these would not change the end data, right?

Original image: AMNSY , logo: Cassava.

Elisabeth Bik confirmed the concerns reported to the FDA, and challenged by the Cassava statement, searched herself and then found more, much more. She later published a blog post detailing some of the new evidence.

Blue boxes mark very similar panels which differ by brightness only while representing different experiments. On top of that, Bik spotted that the the Gai panel in Figure 2 looks fishy. It does indeed appear that bands were digitally pasted or selectively manipulated otherwise in Photoshop.

Then there were even more duplicated gel bands. Where the Labaton Sucharow letter reported “Telltale signs that the Gα bands in Figure 5a likely come from different gels“, Bik followed up on the “Additional Suspicious Western Blots” in Section E and found:

  • Blue and green boxes: It was noted in the report mentioned above that some of the “double decker” bands look similar to each other. The resolution is low, but maybe the authors could take away these concerns by showing the uncropped blots, if they still are available?
  • Pink boxes: An additional concern not noted in the report is that two of the G-alpha bands, representing seemingly different experiments (Morphine vs NLX), look quite similar, while their surrounding bands are very different.
  • Orange arrows: some artifacts around bands suggestive of splicing.

That paper doesn’t have a conflict of interest section, apparently back in 2005 this concept was not invented by Elsevier yet.

As mentioned above, that Wang et al 2005 paper contained data later reused in Wang et al 2010:

Hoau-Yan Wang, Kalindi Bakshi, Changpeng Shen , Maya Frankfurt, Caryn Trocmé-Thibierge, Philippe Morain S 24795 limits beta-amyloid-alpha7 nicotinic receptor interaction and reduces Alzheimer’s disease-like pathologies Biological Psychiatry (2010) doi: 10.1016/j.biopsych.2009.09.031 

That study with a proprietary drug was funded by another pharma company, Servier, which also paid Wang as consultant. Bik found that paper was also falsified:

Figure 1A appears to show a lighter background around some, but not all bands in the top a7nAChR blot. A similar lighter area is visible around all bands in the lower blot.

Such things happen when a gel image gets assembled or otherwise modified in Photoshop, with the purpose of data forgery.

Moving on to the next paper:

Hoau-Yan Wang, Maya Frankfurt , Lindsay H. Burns High-Affinity Naloxone Binding to Filamin A Prevents Mu Opioid Receptor–Gs Coupling Underlying Opioid Tolerance and Dependence PLoS ONE (2008) doi: 10.1371/journal.pone.0001554

The paper mentions as conflict of interests that “This study was supported by Pain Therapeutics, Inc. and LHB is an employee of this company“, but Wang forgot to mention that he was paid by Pain Therapeutics (now Cassava) as advisory board member.

The lawyer’s report criticised gel splicing and added “Figure 7a of that paper appears to show two IDENTICAL panels (red arrows) for what are reported as different experiments.

Bik: “Figure 7A: Red boxes: In thee MOR row, the NLX and FLNA panels appear to look identical.
Blue arrows: Some sharp background transitions around bands, suggestive of splicing or patching.

Cassava rebutted such evidence with this statement:

Fiction: Cassava Sciences’ Western blots data appear overexposed and highly processed, evidence of image manipulation.
Fact: High quality bands are supposed to look sharp6. Smudged bands can be evidence of inexperience, depending on levels of protein in the band.

I love this. If you gels lack sharp edges around the bands, it’s because you are an inexperienced loser. This pigheaded arrogance is breathtaking, do they really think everyone else is as scientifically illiterate as they are?

The next discussed paper about curing Alzheimer’s with Filamin A was this:

Hoau-Yan Wang , Kalindi Bakshi , Maya Frankfurt , Andres Stucky , Marissa Goberdhan , Sanket M Shah , Lindsay H Burns Reducing amyloid-related Alzheimer’s disease pathogenesis by a small molecule targeting filamin A The Journal of neuroscience (2012) doi: 10.1523/jneurosci.0354-12.2012

At least here, conflicts of interests were declared: “L.H.B. is an employee of and H.-Y.W. is a consultant for Pain Therapeutics, Inc.“. But not the massive fraud in the presented data!

The Labaton Sucharow letter explains:

Bik: “In Figures 6A and 6B, the IRb bands (top blots) appear to be irregularly spaced, and several bands are very similar in shape.

In Figure 1a, the four Filamin A bands in the top set are more similar to each than can be expected by chance and appear to be duplicates. The images at right are magnified, showing that the pixels containing the bands are essentially identical. Additionally, the blots are not aligned and the spacing is irregular. Because FLNA is a large protein (~290kDa), it does not migrate in the gel very far; therefore, this degree of misalignment is suspicious. Moreover, the thin white halos surrounding each band are concerning. There are optical reasons why a halo (or ringing artifact) could occur, but this artifact is most common when components from multiple images are combined using photo editing software. This halo artifact is more prominent in the questionable blots, and extends in some cases into the frame around the blot which is hard to explain as an
optical phenomenon.

This was Cassava’s retort:

Fiction: “Halo” effects in certain bands indicate fraud.
Fact: A “Halo” effects in certain bands is a direct result of very dense dark loading control bands.7

Fiction: Unusual looking bands on Western blots were pieced together from multiple sources.
Fact: Proteins can and do stick to the side of a lane and migrate that way, resulting in ‘candy-wrapper’ appearance or other fictional images.

It wasn’t the “loading control bands” which have a halo effect, even outside the gel. And the “‘candy-wrapper’ appearance” derives from digital gel band splicing, where some kack-handed fraudster accidentally cuts into neighbouring bands. But yes, I agree, the images presented in those papers are “fictional“.

Bik found more, like the completely fake western blots of IRbeta in Figures 6A and 6B, which were most obviously assembled in Photoshop, sometimes from copy-pasted bands:

Bik: “The IRb blot in Figure 6A in more detail shows that the spacing between the bands is irregular:
Bik: “A detail shot of the IRb blot in Figure 6B shows similar irregular spacing and similarity in band shapes. Several bands have a particular, shoe-like appearance.

Figures 9A and 11 A proved to be fraudulent disasters also:

Those above are fake western blots, made with one single band copy-pasted several times, as the arrows highlight. To add some more colours to that misery, Bik found a recycled immunohistochemistry image, to stand in for different antibody stainings of different experiments.

On to the last paper criticised in the lawyer’s letter to FDA!

Hoau-Yan Wang, Kuo-Chieh Lee , Zhe Pei , Amber Khan , Kalindi Bakshi, Lindsay H. Burns PTI-125 binds and reverses an altered conformation of filamin A to reduce Alzheimer’s disease pathogenesis Neurobiology of Aging (2017) doi: 10.1016/j.neurobiolaging.2017.03.016

The Figure 12 of that Wang et al 2017 paper contains a skilfully falsified western blot. Impressive is that Cassava sees no problem with same gel having either 12 lanes or 13, depending which protein is shown:

In Figure 3, Bik reported more:

One of the bands representing a 10-month sample, in the right blot, appears to be surrounded by a rectangle of a different background than the rest of the blot.

That is because that gel band was digitally inserted in Photoshop, and/or selectively modified inside the rectangle area.

Bik then found similar issues in Figure 10B, gel bands digitally inserted, likely to once again to replace undesired real results:

Also this study’s mouse behavioural data in the so-called Y-Maze experiments was questioned, because “if the result were legitimate, the drug treatment changing the mice’s behavior to closer to 50% spontaneous alternation (i.e., closer to random) would be more accurately interpreted as evidence of worse memory performance.

Cassava reacted with:

Fiction: Changes in the Y-maze test for transgenic mice could be interpreted as a decline in cognition.
Fact: A panel of independent, peer-reviewers believe these changes represent an improvement, along with significant improvements in two other behavior tests.

Which basically means, haha, it doesn’t matter if our results make sense, they passed peer review so you are legally not allowed to criticise them anymore. I guess same applies to the Photoshop fabrications?

Indeed, that paper, as well as the above Wang J Neuroscience 2021 plus Wang et al J Neuroscience 2009, all passed peer review, despite being biologically improbable, as the Labaton Sucharow letter explains:

In one key line of experiments, the authors report that this entire mechanism can be observed in post-mortem human brain tissue from subjects with
Alzheimer’s disease and neurological controls. […] In these experiments, post-mortem human brain tissue is warmed from -80°C to -20°C and chopped into 200micron x 200micron x 3mm blocks with a McIlwain chopper (as a side
note, a McIlwain chopper doesn’t effectively cut frozen tissue). The resulting chopped tissue is treated with β-amyloid and the experimental drug for 1 hour. They then report a massive increase in tau phosphorylation (modification of the tau protein by enzymatic addition of a phosphate group to the protein; up to 10 fold) from β-amyloid treatment in untreated samples; and that tau phosphorylation was blocked by addition of PTI-125. It is unlikely that the enzyme
responsible for phosphorylation would survive the initial -80°C freezing step. Moreover, the phosphorylation experiments are reported to have been performed at 4°C, but it is unlikely that the enzyme responsible for phosphorylation would be active at 4°C (enzymes generally work best at body temperature—37°C)

Indeed, valid points, which suggest either that the peer reviewers were either not reading the paper they approved, or were incompetent and scientifically illiterate themselves. But the situation was even worse:

The methodology for the post-mortem human brain experiments among the three studies are virtually word-for-word identical. The age and post-mortem interval for the groups of subjects are the same (down to the decimal points) in each of the three papers. It is therefore reasonable to assume the same human brain specimens were used across the studies from 2008-2017, so the results are premised on the enzymes in the human brain extracts remaining active up to 13 hours post-mortem before freezing, remaining active after nearly 10 years in frozen archival without any advanced cryopreservative techniques, and being active at 4°C.”

The company retorted with:

Cassava Sciences is not aware of an industry-wide ‘expiration date’ on human post-mortem brain tissue that is properly collected, processed and stored.

I wish they would instead explain how they made the native brain enzymes work under such conditions though.

Those were not the only problematic papers by Wang. Here one with the company’s founder and CEO Remi Barbier and the Chief Medical Officer Nadav Friedmann as co-authors:

H.-Y. Wang, Z. Pei , K.-C. Lee , E. Lopez-Brignoni , B. Nikolov , C.A. Crowley , M.R. Marsman , R. Barbier , N. Friedmann, L.H. Burns PTI-125 REDUCES BIOMARKERS OF ALZHEIMER’S DISEASE IN PATIENTS The Journal of Prevention of Alzheimer s Disease (2020) doi: 10.14283/jpad.2020.6

Bik criticised that the paper was peer reviewed in just 6 days. And she found a problematic gel in Figure 3A:

  • Slanted blue arrows: Some bands appear to float over the background, surrounded by a white halo, and with a sharper appearance than other bands
  • Pink arrows: The right-most band in the pT231Tau lane appears to be surrounded by a rectangular box with a different background appearance as the other lanes.”

Jay J. Paquette , Hoau-Yan Wang, Kalindi Bakshi, Mary C. Olmstead Cannabinoid-induced tolerance is associated with a CB1 receptor G protein coupling switch that is prevented by ultra-low dose rimonabant Behavioural Pharmacology (2007) doi: 10.1097/fbp.0b013e3282f15890 

Bik found problems with Figure 4A.

  • Orange boxes: Two of the double decker G alpha bands appear to look similar, if one of them is flipped horizontally. Note a slanted stripe in the middle of the top band.
  • Green boxes: Two other double decker bands in the bottom left blot look similar
  • Teal boxes: Two single bands in different G alpha blots look similar

Presumably, if your western blots lack duplicated bands, it is the sign of your “inexperience”.

Kalindi Bakshi, Raminder Parihar, Satindra K. Goswami , Melissa Walsh , Eitan Friedman, Hoau-Yan Wang Prenatal cocaine exposure uncouples mGluR1 from Homer1 and Gq Proteins PLoS ONE (2014) doi: 10.1371/journal.pone.0091671

Bik found two figures very skilfully falsified. For example, Figure 2A.

In the Homer 1 / Frontal cortex blot, unexpected sharp horizontal and vertical background transitions appear to be visible. Of particular note, the top band in the right-most lane appears surrounded by a rectangular box of a different background. Shown with blue arrows.

That is a very fake western blot, assembled by some fraudster in Photoshop. Blame all that cocaine in Wang’s lab!

Finally, one very new Wang paper (The authors declare no competing financial interests) was flagged by an anonymous PubPeer commenter:

Gavin M. Meade , Lily S. Charron , Lantz W. Kilburn , Zhe Pei , Hoau-Yan Wang , Siobhan Robinson A model of negative emotional contagion between male-female rat dyads: Effects of voluntary exercise on stress-induced behavior and BDNF-TrkB signaling Physiology & Behavior (2021) doi: 10.1016/j.physbeh.2020.113286

There are two clear splices, where they have managed to cut into the band itself when copy-pasting.
There are similar issues with Figures 7b, 8a, and 9a

Section E of the lawyer’s letter to FDA is about “Six Additional Areas of Concern“, discussing “suspicious” scientific claims and flagging “Additional Suspicious Western Blots“, the latter largely confirmed by Bik.

Part D asks FDA to suspend Cassava’s scheduled phase 3 clinical trial NCT04994483 with 750 participants, and to audit all past clincial trials this company performed. NIH and the New York University are asked to investigate Wang’s research, the journals are invited to retract the falsified papers.

The Labaton Sucharow lawyers also discuss irregularities in the trial data, like this:

“it seems that the primary biomarker data set we have with simufilam in Alzheimer’s disease that was entirely produced and finalized by an external lab found that the drug had no effect on clinical biomarkers. Cassava replaced this with a reanalysis that was finalized by an academic lab (presumably Dr.
Wang) and showed that simufilam showed remarkable benefit. Second, plasma biomarker data from these same patients, which were just presented by Cassava Sciences, contains evidence of manipulation. If there’s no biomarker signal, and there is apparent misrepresentation of clinical data the continuation of the ongoing Cassava trials may put patients at risk without the claimed evidence of biomarker benefit.”

Cassava’s reply to it sounds like what Chinese cheaters post on PubPeer blaming an “external company”:

Fiction: Biomarker data is generated by Cassava Sciences or its science collaborators and therefore are falsified.
Fact: Cassava Sciences’ plasma p-tau data from Alzheimer’s patients was generated by Quanterix Corp., an independent company, and presented at the recent Alzheimer’s Association International Conference1.

Problem is, Quanterix was not prepared to play the scapegoat and was quoted:

“In Friday’s statement, Quanterix said it is “widely recognized for its commitment to business integrity and to upholding the highest standards of quality.” Quanterix’s stock rose 4.5% in premarket trading, while Cassava shares tumbled 21.2%”

Apparently unconvinced by Cassava’s explanations, The City College of New York opened a research misconduct investigation of Wang’s papers. Tony M. Liss, Provost and Senior Vice President for Academic Affairs, confirmed it to me:

The College takes accusations of research misconduct very seriously. When such an accusation is made the College Research Integrity Officer follows the CUNY Policy Regarding the Disposition of Allegations of Research Misconduct . Until that process is completed, we are unable to comment or respond to inquiries.

Maybe this is why Cassava started to distance themselves from Wang in their next statement from 27.08.2021:

No, the preclinical and clinical foundations linking Filamin A to Alzheimer’s disease do not derive only from the publications of Drs. Wang and Burns.

As if that proves anything. The Seeking Alpha article (allegedly written by a “Joe Springer”, if you believe that) lists several research papers on Filamin A (who gave those to Joe?), and then warns: “Trials are only halted for safety, and simufilam is shown safer than placebo, there is no chance the FDA will act on the petition’s requests.

Apparently they think research fraud is not a reason to suspend a clinical trial.

The above mentioned Athira Pharma placed their own founding CEO on leave after Leen Kawas’ papers were reported for data manipulation. But Cassava Sciences keeps lashing out at critics instead of dismissing Wang and Burns. This pharma startup seems to be at best utterly ignorant how science is done properly, and at worst, well, you saw the gel pictures and Cassava’s press releases. Not really reassuring to the investors, no wonder that the stocks are in freefall. What will happen to the clinical trials now?

Update 29./30.08.2021

On 29 July 2021, Cassava proudly announced interim results of an open-label clinical trial with Simufilam (PTI-125) with 150 participants. The trial is described to have started in March 2020, and was not only unblinded, but it also didn’t have a control arm (which makes that whole trial rather pointless).

The description of the NCT04388254 trial, which somehow managed to be Open-Label (unblinded) and quadruply blinded, as well as both with and without control arm, is confusing at best (hence my correction of the previous update):

Approximately two hundred (200) patients will be enrolled into the study. All participants will receive open-label simufilam 100 mg b.i.d. for a year. At Month12, participants will be randomized (1:1) to continue taking simufilam 100 mg b.i.d. or to be switched to placebo for 6 months. At Month 18, all participants will enter a final 6-month treatment period of open-label simufilam 100 mg b.i.d.

The switch from “A 12-Month, Open-Label Safety Study of PTI-125” to “Simufilam Followed by a 6-Month Randomized Withdrawal and 6 Additional Months Open-Label” happened on 30 July 2020. Also, the number of patients to be recruited jumped from 100 to 200, but now the press release changed it to 150: “The open-label study has completed its target enrollment of 150 subjects“. It all looks like an insane trick to somehow turn something extremely biased and unreliable into a gold standard of a blinded randomised controlled clinical trial.

The now announced open-label trial was founded by NIH in 2020 (grant #1R44AG065152-01) as a continuation of the previous open-label trial by Cassava NCT03748706, which took place March-May 2019 and treated 13 patients. Its results were published by our trustworthy friends Wang and Burns (the latter is listed as principal investigator of both the old and the new open-label trial):

Wang HY, Pei Z, Lee KC, Lopez-Brignoni E, Nikolov B, Crowley CA, Marsman MR, Barbier R, Friedmann N, Burns LH. PTI-125 Reduces Biomarkers of Alzheimer’s Disease in Patients. J Prev Alzheimers Dis. (2020). doi: 10.14283/jpad.2020.6

I apologise for the confusion in the update before, I never saw a quadruple-blinded but open-label while one-arm but placebo-controlled trial with 150 or maybe 200 participants before 😉

Update 30.08.2021

Elisabeth Bik wrote a follow up, and she found several inconsistencies in the Cassava clinical data from the contested phase 2 trial NCT04079803 and its results presented as poster Wang et al at a conference in July 2021. Bik notes:

Analysis: E. Bik

The poster states that 64 patients were included in the study and randomly assigned to three groups. There are no details given about how many patients were assigned to each group, but we would expect roughly 20 people per group. Yet, Figure 4 only shows 20, 15, and 17 data points for the placebo, 50 mg, and 100 mg Simufilam groups, respectively. That is a total of 52 patients. What happened to the 12 other patients?

Well, maybe these patients were all misbehaving outliers, you know… Look, two of them left the placebo group eventually, one disappeared, the other felt so well that participant joined the treatment group:

While Figure 4 shows 20/15/17 (sum=52) data points for the three groups, Figure 5 appears to show 18/15/18 data points (sum=51). The numbers of the placebo and 100 mg treatment groups therefore do not match.

Actually, the patients walked in both directions. Those whose Alzheimer’s decease worsened, got up and joined the placebo group:

Of particular note, in Figure 5, the P-tau181 value from a patient in the 100 mg treatment group went up from ~2.1 to ~5.2, which is an increase of 150%. In other words, one of the patients in the 100 mg treatment group showed a large increase of the Alzheimer’s disease biomarker . Yet, this particular data point is missing in the 100 mg treatment group in Figure 4. Instead, the 150% increase data point is included in the placebo group.

Watching all that pathetic data fudgery is PAINful, pun intended.

A reader pointed me to this preprint with same trial results:

Hoau-Yan Wang, Zhe Pei, Kuo-Chieh Lee, Yaneicy Gonzalez Rojas, Tamara Doehner, John Puente, Patrick Sciara, Brian Beck, Evelyn Lopez-Brignoni, Boris Nikolov, Carrie Crowley, George Ben Thornton, Remi Barbier, Nadav Friedmann, Jeffrey L. Cummings, Lindsay Burns Effects of simufilam on cerebrospinal fluid biomarkers in Alzheimer’s disease: A randomized clinical trial ResearchSquare (2021) DOI: 10.21203/

Fig 1. Four patients were removed from treatment arms for being naughty.

Update 4.09.2021

According to this source (apparently based on this paywalled STAT News article), Remi Barbier and Lindsay Burns are married. So now we know why Barbier keeps defending the obvious Photoshop forgeries his wife published with Wang:

I am aware that the allegations have caused a storm of opinions and counter-opinions on the internet around the fine visual features of photograph of certain Western blots. We all know that once a photograph is on the internet, the pixels that make up that photograph can easily be Photoshopped, cropped or otherwise distorted to mean anything you want it to mean.
Furthermore, internet photos are resolution dependent. This means an internet photo can quickly lose quality and look blurry or pixelated, or whatever. I don’t trust the authenticity of photos on the internet, and neither should you.

It must be a global conspiracy against Cassava which involves everyone in scholarly publishing and academia, going back many years already?

Update 10.11.2021

On 4 November 2021, Cassava issued a press release regarding the disastrous paper paper Wang et al J Neuroscience 2012 (discussed above):

“The Journal of Neuroscience authorized Cassava Sciences to share a statement on this matter, reprinted in full below:

“The Journal of Neuroscience follows COPE [ C ommittee o n P ublication E thics] guidelines and takes any claims of misconduct very seriously. In response to allegations of data manipulation in JNeurosci 2012;32:9773-9784 the Journal requested raw data, including images of original, uncropped Western blots. The Journal determined that there was one duplicated panel in Figure 8 and a Corrigendum was requested and will be printed. No evidence of data manipulation was found for Western blot data.”

I was very curious about those mysterious uncropped blots. Pity the journal’s Editor-in-Chief Marina Picciotto, professor of neuroscience in Yale, ignored all my emails.

Now, on 10 November 2021, the Erratum appeared:

The original, uncropped blots of loading control bands in Figure 6, Aand B, are shown below.
The original, uncropped blots for b-actin in Figure 9Aare also shown below. The left image is the higher-resolution image with the additional bands cropped out, as seen in the full image on the right.

Here are those “original, uncropped blots”, lo and behold (I merely boosted the levels):

Now, Dr Picciotto and her editorial colleagues are surely the real experts, but what the actual f*** are these pictures, really?

Observe that the gel bands go from one edge of the membrane to another. Meaning, if those were real gels (not likely):

  • for the two top gels with 10 lanes each there never was any marker lane loaded. Do I really need to explain to DOCTOR Picciotto why this is important?
  • for the bottom gels (“uncropped” on the right) not only there is no marker lane but they even cut the membrane to blot exactly only the 9 gel lanes they loaded and not the last, empty lane where they could have loaded a marker. Also, what is that shadow which accidentally exactly fits the cropped version of that same gel on bottom left (also spotted by Bik)? The background pattern is also different between cropped and uncropped actin.

But if our Yale professor says this makes sense, who is the failed scientist here?

Update 17.11.2021

Cassava made it into The Wall Street Journal, because the company with “the sixth-best performing U.S. stock this year“, once valued at $5 Billion, is now under investigation by the Securities and Exchange Commission (SEC), the US government’s stockmarket watchdog. Cassava is also under investigation by National Institutes of Health (NIH), who may want to recover their $20 million grant money.

We now also know who submitted that FDA letter:

“The petition’s authors are two physicians who said they came to doubt Cassava’s research and have shorted its stock, betting the share price would fall once investors recognized the problems they found, they said. David Bredt, a biotech entrepreneur and former neuroscience research chief at Johnson & Johnson and Eli Lilly & Co., and Geoffrey Pitt, a cardiologist and professor at Weill Cornell Medicine, wrote that Cassava’s research, published in several different scientific journals, include images of experiments that appear to have been manipulated using software such as Photoshop.”

Update 21.12.2021

There is a follow-up article, with even more Cassava fraud, and even more embarrassment for regulatory authorities and scientific journals!

Cassava Sciences never replied to my emails when asked to comment about the growing PubPeer evidence or the clinical trial registration issues.

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83 comments on “Facts and Fiction of Cassava Sciences

  1. zensciencecowboy

    Great article. Maybe a bit too much molecular biology for the stock traders. For those interested in better science, someone posted the structure of the drug Simuflam:

    Does anyone understand the binding curves they published? How does FEMTOmolar affinity binding not get displaced by 100X excess cold ligand?


  2. Not fiinding a femtomolar affinity speaks of inexperience!


  3. NMH, the failed scientist and incel

    Streptavidin/avidin with biotin could be femtomolar affinity, its considered practically irreversible with little off rate.


  4. Greetings. Appreciate your insight in regards to the WB findings.

    Hopefully I can clarify some potential reasoning behind the confusing open label, then placebo controlled, then open label study.

    Clinically, that study provides some good information and the strange structure can be explained by an understanding of timing of the study (note, multiple assumptions are made below, but I think it is mostly accurate).

    The study started out as a “simple” open label phase 2 study of Simufilam. As the company obtained more funding, they were able to increase the sample size of the study.

    As they obtained the results, they found a stronger impact on the disease process than expected.

    This raises an interesting question, does treatment with Simufilam simply improve cognitive functioning, or does Simufilam have a disease modifying impact on AD? One way to show this is to take a population of patients on drug, then take them off drug and see if they return to their previous baseline. Re-introducing drug after 6 months, you can then see if they return to their higher level of functioning or are improved, but not as well as the group that continued on drug throughout.

    Complicated structure and there are certainly multiple issues with the study structure, but I think understandable why it was structured that way.


    • Yes! That makes sense!
      And they also rigged the results of the phase 2 RCT by removing and shifting participants as not to shock the world with how groundbreakingly positive their results really were!


  5. Marco Hunter

    Leonid – Not a big fan of your writing style either, guess it’s designed to stir people up. But let’s skip that and talk turkey.

    1.) First, let’s talk brain bleeds, as in, side effects of Biogen’s and Lilly’s drugs. Why did the petitioner not file a safety petition against those? I mean, he’s a gravely concerned guy, right?

    2.) Let’s say Cassava’s stuff is faked, do you seriously think they would further fake their way thru a stage 3? If they knew it was fake, and stage 3 would fail, shouldn’t they have sold by now? I guess your argument is they are even stupider than you thought?

    3.) This Wang guy, I mean he’s so not cool. Basically, community college guy, probably brings his lunch to work in an f brown bag. All the cool hedgies, Harvard, Yale MDs, they’ll kick his ass. He can’t do **** right, obviously. By the way, the picture you start with – demonstrates your asshat bias right off the bat.

    4.) Curious, for the heck of it, can you name any scientific or medical hypotheses that were dismissed or laughed at or ignored, before eventually being found correct?

    5.) And in terms of fraud, Elizabeth ought to be suing you.


  6. The western blots are so poorly photoshopped the fraud hides in plain sight (well once the law firm, Dr. Bik and you highlighted where to look). A company based on partially manipulated research (and potentially guided by a fraudster) performing clinical trials is highly problematic. The petulant and nonsensical answers Cassava provided speak loudly about their lack of professionalism – I am shocked such a mess ever got funding at all.

    As your wonderful collection of cautionary tales showcases the personal consequences for fraud in academia are usually minor, but maybe if duped investors or patients are involved the screws get tightened a bit further.

    Only the enzyme part I don’t quite agree on: I cannot speak on this particular enzyme, but activity of many enzymes is well preserved in frozen tissues (-80C or lower) for a long time in absence of cryoprotectants – although decades might be stretching it, it’s not implausible with high baseline activity. To wit, many (recombinant) enzymes can be preserved frozen for years once reconstituted. Not that that makes any of the other criticisms less valid.


  7. It’s all a giant conspiracy!


  8. I have been reading all comments and could’nt resist to insert my opinion about all of this.

    James has been very open and truthfull and professional and after reading Leonid comments, I am sorry to say, but it is almost humiliating to see when a journalist approaches a subject without fully researching and knowing all the facts.

    Credibility is what we are seeking here. Isn’t it?

    When you write something without required research and make a mockery of a practice that has been known to the scientific community, such as “open label trials” and dismiss such trials which has shown to be effective research methods in clinical trials for the past two decades (& growing), without even trying to search the subject in research reports, you are perceived as either a lazy employee or an ignorant journalist or in my humble opinion, intellectually challenged (please excuse my honesty).

    I came to this conclusion, especially when you use the word “INSANE” without knowing what you are talking about.

    Journalists are judged by their writings and one would hope a well paid one like yourself doesn’t write something that could vanish his credibility.

    Time is the ultimate currency and credibility is always relevant.



  9. I had a closer look at fig 9 above, the results for the working-memory Y-maze test. Usually, this test is used to measure “spontaneous alternation”. This is the tendency of rodents to prefer a new maze arm over one that has previously been visited. In order to alternate, the animal has to be able to orient itself in space and remember which arm has been visited and which one not. Chance levels are 50% (that does not necessarily mean that the animal cannot do this task, just that it does not do it). In the present case, the 6-mont WT animals show a score way below 50%, meaning that they actually actively avoid entering a new arm but instead prefer the already visited arm. This is unusual, but not unheard of. It still means that these animals have a functional spatial working memory, otherwise they would not be able to distinguish between the two arms (an have a score around 50%). It’s difficult to say why these animals don’t alternate but do the opposite (“perseverance”), one reason might be elevated anxiety, making them fearful to enter new spaces and prefer previously visited ones. Now looking at the 3xTgAD 6-month animals, we indeed see a higher score for the treated animals, but in this case “higher” doesn’t equal “better”. The correct metric to evaluate this test is how much the score differs from chance level, 50% The treated animals are closer to chance levels than the untreated ones. What this exactly means I cannot say, perhaps they are mess anxious, but in no case does this indicate improved memory.
    So I don’t know who were on this “panel of independent, peer-reviewers”, but either they missed this or (like the authors) had no clue on how to interpret a Y-maze spontaneous alternation test…


    • Interesting point. Another non-exclusive possibility is a better habituation as defined by Bolhuis, in a paradigm where for unknown reasons you suggested (stress reactivity etc.), mice were more prone to stick to the familiar arm. In the TgAD mice, a faster habituation, possibly interpreted as better learning, could thereby lead to faster/greater habituation and promote exploration of the unfamiliar arm.


  10. Press release by Cassava re: Wang et al J Neurosc 2012–5956678691554882.html

    “Nov. 04, 2021 (GLOBE NEWSWIRE) — Cassava Sciences, Inc. (Nasdaq: SAVA) has been informed by the Journal of Neuroscience that there is no evidence of data manipulation in an article it published in July 2012 describing a new approach to treating Alzheimer’s disease 1 . The peer-reviewed article was co-authored by scientists and academic collaborators for Cassava Sciences and is foundational to simufilam, the Company’s lead drug candidate for the proposed treatment of Alzheimer’s disease. […]
    In August 2021, a law firm 2 representing anonymous short sellers submitted a Citizen Petition to the U.S. Food and Drug Administration (FDA) that alleges, among other things, data manipulation in Western blots in a science article published by the Journal of Neuroscience in July 2012. (Western blotting is a complex laboratory technique used to separate and measure proteins). In response to this and similar on-line allegations, the Journal of Neuroscience requested raw data for the article, including images of original, uncropped Western blots. Having received that data and completed its review, the Journal of Neuroscience states: “ No evidence of data manipulation was found for Western blot data. ” One human error that does not impact data conclusions was identified (a duplicated panel in Figure 8B of the article), and the publisher is expected to print a correction.

    The Journal of Neuroscience authorized Cassava Sciences to share a statement on this matter, reprinted in full below:

    “The Journal of Neuroscience follows COPE [ C ommittee o n P ublication E thics] guidelines and takes any claims of misconduct very seriously. In response to allegations of data manipulation in JNeurosci 2012;32:9773-9784 the Journal requested raw data, including images of original, uncropped Western blots. The Journal determined that there was one duplicated panel in Figure 8 and a Corrigendum was requested and will be printed. No evidence of data manipulation was found for Western blot data.” “


  11. For the sake of better science, but I am really totally mystified by your statement 10.11.2021 “Cassava Sciences never replied to my emails when asked to comment about the growing PubPeer evidence or the clinical trial registration issues”….?

    that is so out-of-caracter.
    and he could have at least answered you with some post-truth bullshit to quickly claim some cheap moral victory for ‘putting you right’ (Trump-way)

    And then journal’s Editor-in-Chief Marina Picciotto, professor of neuroscience in Yale…ignoring emails about the growing PubPeer evidence or the clinical trial registration issues?
    Yale….not open for better science any more??

    –>if scientists are wrong (you, or anybody) they deserve to be corrected…for the good of all!

    So thanks for all your voluntary ‘struggles’ so far, and hope they will (one-day) disclose


    • I now wrote to Society for Neuroscience president and its Scientific Publications Committee, with J Neuroscience editors in cc.
      Most likely nobody will reply again. But if at least one of them is not a chickenshit and has some decency left, there will be some infighting.


      • It seems that the concerns have been duly mentioned to CUNY who is actively investigating this case, with its ORI…. this is the due process and ORI has the authority and the tools to look into these allegations. Journals on the other hand are not qualified investigators, but are supposed to report issues to ORI, not decide a priori what really happened. Debatable but it’s the US process, and mob justice can be treacherous. So ignoring a blogger’s emails does not seem out of place here, especially when the goal seems (is?) to make things “salient” and click-baitable; the case is pending and JofN clearly said they are waiting for the results of the investigation… without preemptively judging. Writing a blog online is different from being a journal editor with actual responsibilities and rules to follow. As for the FDA authorization, people might want to realize that no drugs would be approved on the basis of this paper anyway, because it is just preclinical, in mice…. it’s just complete ignorance of how the FDA works.


      • I’m sorry, what exactly is your problem with my article?


  12. I don’t have a major problem as I think this is an important issue to discuss. And I like (most of) your blog, even the snarky tone. Do my guts feel these are BS blots: you bet. I am rationally 100% certain of it, without knowing the fine details and hearing what the authors have to say/show: no. Should JofN decide it’s bad and yank it? No, because this is an already published article, not a recently submitted manuscript. So before retracting a paper from 2012 (with attached consequences), it has to be duly investigated. And the consequences will only be stronger. JofN has been clear about the process AFAIK. So using condescending attacks against Picciotto (not the editor in 2012 (?)), arguing her competence and actions, mainly because she did not respond to you, seems bitter and inadequate. The case is ongoing.


    • As you know, unlike Retraction Watch, I do not see it as my mission to assure the public the authorities have everything under control. Quite the opposite. Science fraudsters get whitewashed by their universities while journal editors shut both eyes. Both crack down only on whistleblowers.
      As to your point that Dr Picciotto is not responsible: she is, as the current EiC, check COPE guidelines if you don’t believe me. The past EiC has no say here. But Dr Picciotto declared something to be trustworthy “raw data” which is most obviously a pathetic photoshop forgery. Why you protest about my writing to her, is a bit unclear, but whatever.
      Otherwise, scientific evaluation is best left to the community, not to “authorities”. Scientists don’t need SUNY or JNeuroscience to tell them what to think of these fake gels and the explanations the authors provide. This is where I come in: I assemble the evidence online for others to form opinion on.


      • Fair enough – I missed the part about where it said these were “trustworthy gels” as this is not what I read; it seems it was just presented as “here’s the raw gels but it’s being investigated”. Maybe I misunderstood. I know things can get whitewashed by institutions/journals way too well…even when some authors (me) specifically and loudly ask for the retraction of their own tainted papers after discovering that some data may have been fudged. But regarding your post and the comments you made, it almost feels like JofN EIC is responsible for the forgery, hence my initial comments. I get your point, but I also know these situations are difficult for EIC who are not full time on this, and have labs and many other things to handle. I agree that I may have been trigger-happy due to retraction watch’s obnoxious white knight/click bait attitude.


      • Please read again the Cassava press release I quoted.

        The Journal of Neuroscience authorized Cassava Sciences to share a statement on this matter, reprinted in full below:

        The Journal of Neuroscience follows COPE [Committee on Publication Ethics] guidelines and takes any claims of misconduct very seriously. In response to allegations of data manipulation in JNeurosci 2012;32:9773-9784 the Journal requested raw data, including images of original, uncropped Western blots. The Journal determined that there was one duplicated panel in Figure 8 and a Corrigendum was requested and will be printed. No evidence of data manipulation was found for Western blot data.

        In case you wonder what if Cassava lied there as well and J Neuroscience never gave them this statement to be quoted…. well, this is why I wrote to Picciotto. She never replied.


  13. Elisabeth Woeckner pointed out to me who Cassava Sciences collaborates with, as per their own online document:

    “Below is a list of participating research sites for the ongoing open-label extension study of simufilam, an investigational drug candidate in Alzheimer’s disease. […]

    IMIC Research, Inc
    18320 Franjo Rd, Palmetto Bay, FL 33157
    Office Line: (786) 310-7477
    Primary Investigator: Evelyn Lopez-Brignoni, MD
    Study Coordinator: Aimee Cabo
    Office Line: (786) 310-7477

    CEO: Dr. Boris Nikolov
    Office Line: (786) 310-7477

    Nikolov and Cabo are husband and wife, obviously, and mad as two hatters (in pointy white hoods). Check their Twitter feeds (here and here) at your own peril. It’s mostly inane Jesus-worshipping memes with heavy white-supremacist undertones like these:

    Interspersed with far-right ideology plus rabid antivaxxery and covidiocies. I collected among the recent tweets, but you can search further back if you like:

    Now that I convinced you of the clinical and scientific qualifications of these Cassava-collaborating IMIC Research owners, you should know that their principal investigator for the Cassava trial, Evelyn Lopez-Brignoni, was sanctioned by FDA earlier this year. Here is the Warning Letter:

    You failed to ensure that the investigation was conducted according to the investigational plan [21 CFR 312.60].

    As a clinical investigator, you are required to ensure that your clinical studies are conducted in accordance with the investigational plan. The investigational plan for Protocols (b)(4) and (b)(4) required subjects to take (b)(4) of study medication (b)(4), administered as a (b)(4), to demonstrate the efficacy (b)(4). You failed to adhere to these requirements.”

    How could anyone ever take Cassava Sciences seriously?


    • In this regard, I also recommend this read:

      Click to access Cassava-Sciences-SAVA_-Game-Over.pdf

      “Cassava’s prominent clinical research site (whose CEO is coauthor of critical research on Simufilam), IMIC Inc., is co-owned by a former escort, stripper and crack addict with a criminal record for consumption and possession of cocaine.”

      But Aimee Cabo is a born again Christian, so there. Oh, and here is a bizarre story about her in Miami New Times, referenced by QCM. She and her Bulgarian husband were both bankrupt, but now become extremely rich thanks to Cassava money. QCM even sent undercover investigators posing as trial condidates to IMIC and learned: “When asked whether [Nikolov] held any stock, he became uncomfortable and ultimately did not answer.”

      And as for Cassava (named after its owner’s home address):

      “Until 2019 the company used to be called “Pain Therapeutics”. Its only asset then was Remoxy, a pain killer that ultimately failed to gain FDA approval. Both Mr. Barbier and Mr. Friedman were sued for securities fraud5 for their misleading statements about Remoxy’s prospects.”


  14. Pingback: Cassava fraud and Alzheimer’s capitalism – For Better Science

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