NRx Pharmaceuticals seeks FDA breakthrough therapy tag for COVID-19 drug Zyesami
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NRx Pharmaceuticals (NASDAQ:NRXP) said it filed a new request with the U.S. Food and Drug Administration (FDA) for breakthrough therapy designation for its COVID-19 drug Zyesami.
The company said the filing for Zyesami (aviptadil) is for a subgroup of patients with critical COVID-19 with respiratory failure who were also treated with Gilead Sciences' (GILD) remdesivir and continued to progress.
The company added that the submission includes safety data on ~750 patients treated with intravenous Zyesami for critical COVID-19.
NRx said the FDA had previously not granted the drug a breakthrough therapy designation on the filing in September 2021.
The FDA requested new clinical evidence comparing the safety and efficacy of aviptadil relative to other existing therapies for critical COVID-19, such as remdesivir.
The company added that based on the FDA's input, it coducted a post-hoc analysis of its completed phase 2b/3 study focused on ~70% of patients that continued to progress to COVID-19 respiratory failure that also received treatment with remdesivir.
The company said the analysis showed that for these patients, Zyesami showed a highly significant four-fold increased odds of survival compared to placebo at 60 days.
NRx noted that it had filed a breakthrough therapy request with the FDA with this data but withdrew it to add the analysis data from the ~750 patients.
The company said that in February it filed a new emergency use authorization request which was focused on this narrower patient population.
NRXP +3.75% to $2.21 premarket April 21