The more the merrier? The emergence of new oral antiviral treatments for COVID-19
Over the last year, oral antiviral pills have provided an at-home treatment option for patients with mild-to-moderate COVID-19 deemed high-risk of developing severe disease. Pfizer’s Paxlovid currently dominates the market; however, several other companies seek to replicate their success with both Shionogi and Atea showcasing new data for their oral COVID-19 treatments at CROI 2023. Atea presented Phase 1 data for their antiviral, bemnifosbuvir, which showed it may have less drug-drug interaction versus Paxlovid making it easier to use. Further along in development, Shionogi presented new data from the Phase 2/3 trial they used to gain approval of their COVID-19 drug, ensitrelvir, in Japan. This data demonstrated that ensitrelvir has a potent oral antiviral effect in conjunction with a symptom improvement effect. These two companies alongside others such as Gilead seek to further strengthen the utility of oral antivirals.
One key strength point for which these emerging antivirals differ from Paxlovid is the lack of a boosting agent which may mean fewer contraindications and less drug-drug interactions, an important factor when treating high-risk patients presenting with comorbidities.
Variations in these new COVID -19 drugs may also be seen in their dosing schedule as companies seek to reduce patients’ pill burdens down to one tablet a day from Paxlovid’s 6 tablets per day.
Oral antivirals will likely remain an important treatment option for high-risk patients given that COVID-19 continues to evolve. With an increasing number of drugs under investigation, we may see the emergence of a crowded market in stark contrast to where we were only two years ago thus necessitating the requirement for differentiation.