Don’t only bet on the fast Covid-19 vaccines

As companies and countries pour money into the effort to develop Covid-19 vaccines, timelines keep getting more ambitious and dates for delivering a workable immunisation against the virus keep moving up. Yet even with companies such as Moderna Therapeutics Inc and AstraZeneca Plc signalling rapid progress and already enrolling patients in mid-stage trials, it would be quite a feat if we had a stockpile of proven doses by year’s end. That’s a best-case scenario. A longer wait is more likely, and that may seem discouraging. The good news is, there is a batch of treatments in development with a chance of accelerated approval, and they can provide needed relief in the interim.
Dozens of approaches could serve as a valuable bridge, from repurposed drugs to bespoke antibody cocktails. None can replace the value of a vaccine in getting the world back to normal, but the availability of more treatment options for sick patients could help to increase the chances of a faster and fuller recovery, and reduce the lethality of the disease. Two of the most familiar treatments options — the malaria drug hydroxychloroquine and Gilead Sciences Inc’s remdesivir — have recently run into issues over safety and degree of efficacy, but there are plenty more in the pipeline.
When it comes to development, the pathway for treatments is generally smoother than the one for vaccines, which can run into bottlenecks that are fundamentally difficult to break. For one, the fact that innoculations are aimed at healthy individuals means there is a higher safety bar. And the large trials necessary for trying out vaccines would have to occur in places where Covid-19 is spreading substantially to get the random exposure required to test them properly. With multiple candidates in development and ongoing precautions to avoid infection, getting robust data fast may be an issue. Finding volunteers is also an issue for treatment trials, as case counts level off. Still, many outcomes for infected patients can be determined comparatively rapidly. Along with a higher tolerance for side effects in individuals at possible near-term risk of dying, this permits smaller and faster tests.
There are a few significant groups of possible treatments. The first involves repurposing existing drugs such as hydroxychloroquine and remdesivir. Because these types of medicines were originally designed to treat other conditions, they are less likely to produce a dramatic effect. However, if one is useful, it can be deployed quickly. One category within this group doesn’t aim at the virus, but the out-of-control immune response it can cause. Roche Holding AG’s arthritis drug Actemra has shown some early promise and is in larger trials. Researchers plan to test a variety of other medicines that target inflammation. If successful, they could provide several avenues to improved outcomes in critically ill patients. Another idea? Drug cocktails. That’s the thought behind a recently started trial combining remdesivir and Actemra. Several other repurposed combinations, existing flu drugs.
A second category of drug treatments involves a different type of recycling: using the blood of recovered individuals. People who survive Covid-19 develop antibodies against the virus and their donated plasma is already part of treatment regimens for sick patients around the world. Early results look promising, but they need confirmation from randomised trials that are now under way. Scale and variability issues may prevent convalescent plasma from treating millions, so it’s worth boosting identification and collection efforts now even if the benefits of this type of treatment aren’t yet fully determined. A concentrated version under development by Takeda Pharmaceutical also could prove useful.
—Bloomberg

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