Alnylam Pharmaceuticals Inc. (ALNY) shares dropped over 8% in premarket trading on Thursday following the assessment by advisers to the U.S. Food and Drug Administration (FDA) of the company’s treatment for ATTR-CM, a severe heart condition. The FDA advisory committee voted 9 to 3 in favor of the treatment, Onpattro, stating that its benefits outweigh the risks for patients with ATTR-CM. However, analysts believe that the drug’s label may be restricted.
Kostas Biliouris, an analyst at BMO Capital Markets, noted in a Wednesday report that the label for Onpattro will likely be limited to patients who are unable to receive or tolerate tafamidis, the ATTR-CM treatment offered by Pfizer Inc. (PFE) as Vyndaqel and Vyndamax. The FDA advisers seemed to concur with the agency’s stance that the treatment effect of Onpattro is modest, as stated in a note by Oppenheimer analysts on Thursday. They added that even if Onpattro were to receive an unconditional ATTR-CM indication, payors would likely restrict access to those who do not respond adequately to tafamidis.
Despite the setback, both BMO Capital Markets and Oppenheimer analysts maintain outperform ratings on Alnylam shares. They believe that investors are more focused on the potential of Amvuttra, another product developed by Alnylam. As of year-to-date, Alnylam shares have declined by 10.9%, while the S&P 500 has gained 16.4%.
