XBiotech slumps on likely EMA rejection of cancer drug

Canary Wharf, where EMA is based. (Courtesy of Aleem Yousaf CC BY-SA 2.0)

The European Medicines Agency’s (EMA) drug approval committee has indicated it is likely to reject XBiotech’s metastatic colorectal cancer candidate when it holds a formal vote next month. Shares in XBiotech slumped following the news.

The EMA’s Committee for Medicinal Products for Human Use (CHMP) signaled the likely rejection after an informal trend vote. The vote doesn’t represent CHMP’s final position, but the committee typically only changes its verdict if new information emerges before it holds the formal poll. CHMP reached its interim position after meeting with XBiotech to discuss its outstanding questions about the application and the data it contains.

XBiotech said the meeting was primarily focused on the clinical relevance of Xilonix in metastatic colorectal cancer but that CHMP also has outstanding questions about “quality assurance related matters.”

The CHMP members are far from the first people to question the data generated by XBiotech. But, in keeping with his reactions to other critics, XBiotech CEO John Simard has defended the filing in the face of the questioning.

“We believe that the data speak in a clear and resounding voice to clinical relevance of a new antibody therapy in advanced colorectal cancer. We believe that findings from our phase 3 study show that we have developed an important endpoint and methodology to evaluate anti-cancer therapy in advanced stage disease,” Simard said in a statement.

The setback marks another low point in the troubled development of the drug. XBiotech tested the candidate at a single trial site in Poland. The site made several mistakes. In a trial that enrolled more than 300 patients, 25 people dropped out before receiving their first dose, 14 subjects were given the wrong drug—Xilonix instead of placebo or vice versa—and 33 participants completed the study but were never properly evaluated.

Those problems did nothing to deter XBiotech from making big claims about Xilonix when it posted data at ESMO last year. As XBiotech saw it, the data provided “unequivocal evidence” Xilonix could serve as a new treatment for metastatic colorectal cancer. Others saw it differently, including Dirk Arnold, M.D., a member of the ESMO executive board. In a post on ESMO’s website, Arnold picked apart the trial, stating “the jury is still out on whether the study made sense but as the results do not bear close inspection, they also cannot be relied upon.”

XBiotech forged ahead to an EMA filing in the face of such criticism. And it may continue to keep going in the face of criticism from the regulator itself. While companies can use a negative trend vote as an opportunity to withdraw a filing and regroup, XBiotech is considering appealing against the negative decision that emerged from the oral explanation.

Shares in XBiotech fell 21% in premarket trading.