New US label for Biomarin’s Roctavian raises new concerns

Almost three years after the FDA’s initial rejection of Biomarin’s haemophilia A gene therapy, the regulator has finally given a thumbs-up. Supportive sellside analysts focused on the positives: no black box warnings and data showing that at three years the majority of patients continue to respond. But the FDA selected a much more conservative way of measuring annualised bleeding rate, with the label stating a mean 52% ABR reduction at three years, much weaker than the 80% that Biomarin had previously telegraphed. Fading efficacy has long been a concern with Roctavian, a concern that looks set to continue. With slow progress in Germany, where no patient had been treated as of June despite EMA approval in August last year, launch in the US is also likely to be sluggish. SVB analysts took their near term forecasts down yesterday, citing the likely sedate rollout, although like other equity analysts they appear to be optimistic in the longer term. Future demand depends on whether patients choose to wait to see how a rival once-and-done gene therapy performs: pivotal data on Pfizer and Sangamo’s giroctocogene fitelparvovec are due early next year. Meanwhile, Roche's Hemlibra goes from strength to strength, and other effective-looking MAbs are in the pipeline.