AIFA, Italy's drug-regulation agency, said Roche's (OTC:RHHBY) rheumatoid arthritis drug Actemra didn't help patients with early-stage COVID-19 pneumonia in an Italian clinical trial that it authorized.

An interim look at the first 126 patients enrolled in the study found that the drug didn't reduce severe respiratory symptoms, intensive-care visits, or death, compared to standard of care, so the clinical trial was stopped early.

Many ventilators and respirators lined up for use

Image source: Getty Images.

Actemra, which inhibits interleukin-6, is in the same class of drugs as Sanofi (NASDAQ:SNY) and Regeneron Pharmaceuticals' (NASDAQ:REGN) arthritis drug Kevzara, which failed to show an effect in patients with severe cases of COVID-19. Sanofi and Regeneron are continuing to enroll patients who are in critical condition -- meaning they require ventilators, high-flow oxygenation, or treatment in an intensive-care unit.

Interleukin-6 is a cytokine that stimulates the immune system, which, in theory, should help patients fight off the infection. Unfortunately, through a positive-feedback loop, the immune system can hyperreact to the coronavirus that causes COVID-19, resulting in what's called a cytokine storm. The hypothesis is that drugs such as Kevzara or Actemra, which dampen the immune system in rheumatoid arthritis, an autoimmune disease, might help the sickest COVID-19 patients with overactive immune systems that are killing them.

Roche is running a clinical trial of its own, testing Actemra in hospitalized patients with severe COVID-19 pneumonia with data expected this summer. A few weeks ago, the drugmaker also started a clinical trial testing Actemra plus Gilead Sciences' (NASDAQ:GILD) remdesivir, which received Emergency Use Authorization by the Food and Drug Administration last month.

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