According to a study published on Wednesday, covid, an experimental drug initially designed to fight cancer, has halved the risk of death in hospitalized people.
The drug, sabizabulin, seems to be more effective than others approved for critically ill covid patients. Veru has applied to the Food and Drug Administration for urgent approval for the use of the drug, which the Miami company has developed. This will probably add a new weapon to the moderate arsenal available for hospitalized patients, experts say.
“It looks extremely impressive,” said Dr. Ilan Schwartz, an infectious disease specialist at the University of Alberta, who was not involved in the study. “We have a small number of treatments for patients with serious illnesses that improve mortality, but another treatment that can further reduce mortality would be very welcome.”
Dr. Schwartz warned, however, that the trial was relatively small, with only 134 patients taking the drug. “Overall, I think it’s very exciting, although I would welcome larger and independent confirmation research,” he said.
Sabizabulin prevents cells from forming microtubules, vital molecular cables that shuttle components from one part of the cell interior to another.
The drug was originally developed by researchers at the University of Tennessee to fight cancer because fast-growing tumor cells rely on microtubules for their rapid growth.
Two years ago, Veru’s researchers tried Sabizabulin on Kovid. They suspected that the drug could inhibit viral replication, relying on microtubule networks to assemble fragments of new viruses.
They further speculated that the drug would help covid patients fight potential life-threatening pneumonia. This immune response begins when cells detect that they are infected and release alarm-signaling proteins around them. The cells have to push the alarm molecules along their microtubules to get the sound out.
In early 2020, researchers at the University of Tennessee Health Science Center found that Sabizabulin reduced these alarm signals in mouse cells. A few months later, Veru began testing the drug, which was taken as a pill, in humans. In May 2021, it proceeded to a late-stage trial.
The agency wanted volunteers already in the hospital for Kovid. To qualify for the test, patients had to take oxygen or rely on a ventilator. With risk factors such as high blood pressure, advanced age or obesity, they had to be at high risk of covid death.
Patients were simultaneously allowed to receive other treatments that have been shown to be effective in saving the lives of hospitalized covid patients. For example, a steroid called dexamethasone reduces the risk of death by one-third.
In the latest test, 134 volunteers received Sabizabulin and 70 received a placebo. Within 60 days, the mortality rates between the two groups were significantly different: 45.1 percent of the placebo group died compared to only 20.2 percent of those who took the new drug. This difference translated into a 55.2 percent reduction in mortality risk.
Dr. David Boulevard, an infectious disease specialist at the University of Minnesota, warned that the large number of deaths in the placebo group could be a sign that the study was too short to reach a firm conclusion.
“The 45 percent mortality rate in the control group seems to be higher than mine,” he said.
In contrast, in an arthritis drug trial called baricitinib, the researchers gave the drug to 515 covid patients and received 518 placebo. Only 7.8 percent of the placebo group died.
Many antiviral drugs have been shown to be effective in keeping covid patients out of the hospital, but only if they are given early in the course of the disease. Paxlovid, for example, can reduce the risk of hospitalization in immunized individuals with covid risk factors by about 90 percent.
These drugs do not work well, however, on hospitalized patients with moderate to severe covidosis. This is because they only block the virus without controlling the immune system’s response to the escape.
For hospitalized patients, doctors have fewer medications to choose from. In addition to dexamethasone and baricitinib, another anti-inflammatory drug called tocilizumab has been found to help.
When Veru announced its results early in April, the company said it had initially closed the trial because an independent advisory committee had found that Sabizabulin’s benefits were already clear from the data; It would be unethical, they decided, to continue giving some patients placebo.
Although Dr. Boulevard acknowledged the ethical claims of the situation, he also predicted that if the trials were prolonged, the benefits of the drug could emerge as more modest.
“Trials that are closed early routinely over-evaluate the impact,” he said.
Dr. Boulevard noted that the Covid drug Malnupiravi initially reduced the risk of hospitalization from Covid by 50 percent. But in the final analysis that number dropped to 30 percent.
He predicted a similar fate for Sabizabulin. “I would be skeptical that the effect is 55 percent,” Dr. Boulevard said.