After exposure, right, rather than onset of symptoms? So for a respiratory disease with an incubation period of about 5 days, it means taking them daily as a preventative measure. Nice little earner if it works.
After symptom development, to be clear. That said, when dealing with the influenza virus (comparable in that it’s a respiratory virus, has antiviral therapeutics, and a vaccine) the incubation period is often just a day or two- generally far faster than COVID.
Merck’s press release says that participants had symptom onset within 5 days of assignment to a group (drug or placebo), but that could mean 99% of people started within 48hrs and 1% on day 5. So it’s not really clear. Participants also only had mild-moderate symptoms and as I mentioned before, early on the study was also testing the drug in severely ill patients but had to stop because it was not helpful. It should also be noted this interim study was based off data from 775 participants, which is a pretty small sample size (and 50% of their full recruitment sample size of 1,550- which is still smaller than I would expect, especially when there will inevitably be participant drop out- 20% is the average on clinical trials across all drug types).
The potential problem I see is that people will become symptomatic, wait a day or two or three to get tested, then take another day or two to get the result, and then by the time they start the medication it’s too late. It is possible the medication could be started without laboratory confirmation, but that might depend on how expensive the treatment the medicine is. If it costs $100 that’s one thing, if it costs $3,000, thats another. If it’s super expensive, using it unnecessarily would be incredibly wasteful in terms of healthcare spending.
Often times the costs of new medications have little to do with the cost of development and production and instead are based on their value compared to the alternative. If you consider the average COVID hospitalization is $40,000-80,000, decreasing hospitalizations by 50% would mean it has a very high value. Assuming the molupiravir gets authorization it will be interesting to see who will be paying for it (govt vs. insurance).
Looking at Merck’s study’s interim results, molupiravir decreased hospitalization and deaths by 50%. It’s not clear if these participants were vaccinated, not vaccinated, or both- and if the latter how they dealt with that in presenting their results. While 50% reduction is a highly significant result, the effectiveness of the vaccine is far greater in terms of preventing hospitalization and death, overwhelmingly the people hospitalized and dying from COVID are unvaccinated.
Most of the vaccinated who end up in the hospital are people who were unlikely to form a strong immune response to the vaccine in the first place. That’s really where I see a drug like molupiravir having the best utility. I’m afraid there will be a sizable population who believe because this drug exists (assuming it even makes it to market) that it precludes them from getting vaccinated.
At the same time, I’ afraid of the possibility that the drug will have high clinical utility but the FDA either does not authorize or heavily restricts its use because of a fearful assumption it will reduce vaccination participation. Normally this isn’t something that would seriously cross my mind, but some of their judgements in the past couple years have been rather poor and shortsighted.
We’ll have to wait to see the results once the trial is actually completed, peer reviewed, and published before there can be any serious discussion of this. Unfortunately press releases always leave a lot of questions than answers.