Company-stated production capacity for oral antivirals totals ~158 million courses by the end of 2022. Paxlovid and Molnupiravir have been distributed worldwide since the end of Q4 2021 and are now being used in many high-income countries.
Despite availability, uptake of these treatments has been low compared to the supplied amount, and as a proportion of cases. Should uptake remain low, current deals accounting for ~59 million courses are unlikely to be exhausted in 2022.
The remaining production capacity nears ~99 million courses for countries that do not yet have supply deals in place, and are eligible only to source antivirals directly from Pfizer, Merck or Shionogi.
Overall, we see five key factors that could prove to be a hindrance for oral antiviral uptake:
1. Low awareness of treatment options and eligibility
High-risk patients may not be aware of the treatment options available to them if they test positive or are aware they have COVID, or they may be aware of the potential treatment options but not realise that they are eligible for treatment.
Among high risk individuals who tested positive, 66% were aware of oral antivirals, and 36% had sought treatment in the US.
2. Treatment hesitancy
Unvaccinated people, even if aware of treatment options and more likely to benefit from these oral antivirals, may be unwilling or hesitant to use treatments if they have already been unwilling to get vaccinated.
Vaccinated individuals, while still likely to see some benefit, may not feel the need to seek treatment and they may feel vaccination is already enough to prevent severe disease.
Drug-drug interactions are of particular importance with Paxlovid, which has 34 concomitant medications that display interactions and therefor make individuals ineligible for Paxlovid prescription.
Many of these treatments are used to treat conditions which would make an individual high risk, and otherwise eligible for Paxlovid treatment.
Testing, while ramping down significantly even in high-income countries, is still required for oral antiviral prescription, with high-risk individuals requiring a positive test within 5 days of symptom onset to be able to be prescribed oral antivirals due to their fairly limited window of efficacy and mechanism of action in targeting viral replication.
Finally, distribution of oral antivirals remains a major issue, with initial slow production and ramp-up and small initial deliveries of drugs. Lack of access to infrastructure and urban population centres is a particular issue in low-income countries, which have a higher proportion of their population living in rural areas, and thereby have more limited access to prescriptions.