Alleged Misconduct in Amgen-Acquired ChemoCentryx's Tavneos Trial Raises Concerns

In a significant development for the pharmaceutical industry, new evidence has emerged pointing to alleged misconduct in clinical trials conducted by ChemoCentryx, a biotech company acquired by Amgen in 2022 for $3.7 billion. The allegations, stemming from an investor lawsuit, center around the company's drug Tavneos (avacopan), which was approved for the treatment of antineutrophil cytoplasmic antibody-associated vasculitis (AAV), a rare autoimmune disease.

Data Manipulation and Safety Concerns

According to the lawsuit, ChemoCentryx allegedly ignored repeated warnings from a data monitoring committee and manipulated trial results for Tavneos. The plaintiffs claim that Pirow Bekker, M.D., Ph.D., then clinical lead of the Tavneos program, changed the status of five non-responders to responders in the Tavneos group after the trial database was locked. This action allegedly occurred after learning that the study had failed to show superiority at the one-year mark.

The lawsuit also alleges that ChemoCentryx downplayed liver toxicity concerns associated with Tavneos. The independent data monitoring committee for the Advocate trial reportedly warned the company multiple times about understating these risks in public statements. The committee went as far as questioning the New England Journal of Medicine article about the trial results, co-authored by then-CEO Thomas Schall and other investigators.

FDA Approval and Investor Impact

Despite these allegations, Tavneos eventually received FDA approval, albeit with a narrower label than initially planned. The drug's liver toxicity is prominently listed in the "warnings and precautions" section of its FDA label. The approval process was not without controversy, as multiple efficacy and safety issues flagged by FDA reviewers led to a significant drop in ChemoCentryx's stock price and forced the company to amend its application.

Investors who lost money in ChemoCentryx claim that the company knew about the FDA's concerns but publicly stated that interactions with the agency were smooth. The lawsuit alleges that then-CEO Thomas Schall sold approximately $40 million worth of ChemoCentryx shares during the period when the company's stock price was high due to positive readouts from the phase 3 Advocate trial.

Legal Proceedings and Expert Opinions

As the legal battle unfolds, both sides have presented expert opinions. Steven Weisman, Ph.D., global president of clinical and regulatory at consultancy firm Lumanity, contends that the reclassification of patients was part of a prespecified statistical analysis plan and that regulators had access to all information related to the post-lock adjustment of data.

The plaintiffs, however, argue that the changes were not scientifically justified and have presented evidence from multiple experts in the field. The case has attracted additional legal action, with RA Capital joining the fight by filing similar lawsuits against ChemoCentryx and Schall in multiple courts.

As this story continues to develop, it raises important questions about data integrity, transparency in clinical trials, and the responsibilities of pharmaceutical companies to their investors and the public. The outcome of this case could have far-reaching implications for the industry and its regulatory oversight.