After raising serious efficacy questions, the FDA this evening approved Reata Pharmaceuticals’ drug for a rare genetic disease known as Friedreich’s ataxia, which affects the body’s nerves.
While not a cure, the drug known as Skyclarys (omaveloxolone), may slow the progression of this debilitating disease that begins in late childhood and affects about 6,000 Americans and 22,000 individuals globally. The FDA’s approval is based on a positive pivotal trial, showing omaveloxolone beat placebo in terms of a change in what’s known as an mFARS score — a physician-assessed neurological rating scale used to measure FA disease progression.
At 48 weeks, patients treated with omaveloxolone demonstrated a statistically significant, placebo-corrected 2.40 point improvement in mFARS in patients without pes cavus, a preexisting musculoskeletal foot deformity, after 48 weeks of treatment (p=0.014) — meeting the primary endpoint of the study. When pes cavus patients were included in the analysis, omaveloxolone produced a mean statistically significant, placebo-corrected 1.93 point improvement in mFARS (p=0.034).
But it hasn’t been all smooth sailing for Skyclarys, which is a small molecule engineered to bind to a gene called Keap1 to enhance the activity of the protein Nrf2 in order to defuse inflammation.
In a Q2 earnings report, Reata noted that the FDA was concerned about the efficacy of omaveloxolone, which meant a decision on the Plano, TX-based biotech’s key asset took an extra three months to review after the company submitted additional data from its pivotal trial.
In 2019, Reata surprised analysts with a positive readout on its pivotal omaveloxolone trial. However, that initial buzz died a year later when the FDA said the supplemental data from the pivotal trial was not enough, requesting that the biotech run an additional trial.
Reata’s stock $RETA dropped around 30% after the three-month delay, and another 30% yesterday when FDA’s top neuroscience expert Billy Dunn left the FDA, effective immediately.
While there is currently no approved treatment for Friedreich’s ataxia, several biotechs have struggled in trying to treat or cure the disease. In 2016, Horizon’s $50,000 per month drug Actimmune, already approved for two other indications, flunked a Phase III trial for Friedreich’s ataxia. And Larimar Therapeutics’ Phase I program has been on clinical hold after non-human primates died in preclinical testing.