The announcement that a pill from Merck and partner Ridgeback Biotherapeutics kept Covid patients out of the hospital made headlines and moved stocks late last week. But as is so often true when data are released by press release, there are still many questions left unanswered.

Doctors are excited about the medicine, molnupiravir, because a regimen of pills, even one that involves taking several pills twice a day for five days, should be far easier to deliver to patients than current antiviral Covid-19 treatments, which must be given intravenously. But it’s still unclear how widely this treatment will be used. There will also be debate among financial analysts at investment banks regarding exactly how many billions of dollars in sales the new drug will generate.

Here are some things to keep in mind as we learn more about molnupiravir and about other Covid-fighting pills in development at other companies.

One of the reasons that the success of molnupiravir is such a big deal is that there were questions as to whether an antiviral pill could help Covid-19 patients if given early enough. This medicine certainly did, reducing hospitalizations by 50%; it also appeared to have an impact on whether patients survived. That makes it a game-changer. Its success also ups the odds that other medicines will prove effective, too.