IFM | New oral medication to prevent COVID-19 after exposure

Welcome to a special sponsored episode of Inside Family Medicine. I'm your host, Darren Sextro. I'm a member of Team AAFP. Today, we're joined by family physician Dr. Ben Silverberg.

We're excited to be talking about a newly approved oral medication to help prevent COVID-19 illness after exposure that can be important for family physicians and everyone working in primary care.

This sponsored episode is brought to you by Shionogi, the manufacturer of ensitrelvir. Thanks for joining us, Dr. Silverberg.

Thanks for having me. It's great to be here.

So, as you know, it's our tradition, as our audience also knows, with each interview that includes a family physician like you, that we ask the same question. So, Dr. Silverberg, could you please share how you discovered family medicine?

Yeah. I've always been interested in people's backstories, and after a year of teaching English in Ecuador before medical school, I became very interested in global health. In medical school, I tried to find a specialty that would take a holistic view of the patient, where they come from, how they communicate, things like that, and found family medicine.

I'm so glad to have matched into the specialty, to have learned more about social determinants of health, how they affect patient outcomes, and to develop those relationships that inspire trust and facilitate mutual learning.

Thank you for that. So we've been addressing challenges with COVID-19 for years now, and we know the virus is always evolving.

Moving into respiratory season, family medicine teams and patients prepare with, of course, immunizations, but there's a new oral medication that was recently approved by the Food and Drug Administration that may also help families minimize the spread of COVID-19 in their households if one person gets sick. So can you give us the highlights about this new medication?

Sure. It's an oral medication called ensitrelvir, also known as Xocova, that may be prescribed if you or a family member has been exposed to COVID-19 virus.

Households are one of the places that COVID-19 really spreads most easily, and we've all talked to our patients about nonpharmacologic interventions like isolation and masking, but those steps can be difficult to maintain at home.

Up to half of people living with someone who has been infected with COVID go on to develop COVID-19 themselves. So this gives family medicine physicians another option to discuss with eligible patients after a known exposure. Timing is key.

So when family physicians and their teams evaluate this newly approved COVID-19 post-exposure prophylaxis option for their patients, what clinical considerations may come to mind?

What did you take away as you were looking at the study results?

I think the study name was actually really cool.

It was SCORPIO PEP, and this was published in June in the New England Journal of Medicine.

For ensitrelvir, the trial looked at whether the medication could safely prevent COVID-19 illness in people who had already been exposed at home to someone with a confirmed infection.

It was a randomized, double-blind, placebo-controlled Phase 3 trial, and the study included about 2,000 household contacts across several countries, mainly the US and Japan, but also Argentina, South Africa, Vietnam, and there were about 1,000 people in each arm, so in the ensitrelvir group as well as the placebo group respectively.

Of interest, the baseline serology was 98% for S antibodies in both groups, meaning that nearly all patients had some immunity from past COVID-19 infection or through vaccination, even though study participants had not been vaccinated in the preceding six months.

So even with this existing immunity, though, the study still showed the reduction in COVID-19 cases with ensitrelvir.

Overall, given within 72 hours of symptom onset of the index patient, ensitrelvir helped prevent COVID-19 in household contacts.

It demonstrated a 67% reduction in the risk of COVID-19 development through day 10 in those contacts.

Protection was greatest with early post-exposure prophylaxis within s- 48 hours, though, and based on the data, the number needed to treat is about 15.

Shionogi funded and designed the trial, helped collect and analyze the data, and verified its accuracy and adherence to protocol.

What did the study show about this new medication's safety profile?

Among standard risk patients with mild to moderate COVID-19 or asymptomatic infection, ensitrelvir showed strong antiviral activity and reduced acute and respiratory symptoms.

Ensitrelvir is a moderately strong cytochrome P450 3A inhibitor, and it shows mild to moderate reversible decrease in HDL and increase in triglycerides.

Incidence of adverse events during the trial was similar in the two groups, 15.1% in the ensitrelvir group and 15.5% in the placebo group.

Incidence of serious adverse events was about the same, so .2% in each group.

No COVID-19 related hospitalizations or deaths were reported.

So reasonably, what should family physicians consider when deciding which patients may be appropriate for this new medication?

Timing is really important for this medication. The sooner we can identify an exposure and assess eli- eligibility, the more likely patients are to benefit. There's currently a $0 copay for patients with commercial insurance.

Since monoclonal antibodies are administered in an appropriate clinic or infusion center, ensitrelvir offers an outpatient oral treatment option that can be used even in immunocompromised patients. Some patients won't be eligible, including pregnant patients, as well as those taking certain medications ensitrelvir is approved for adolescents and adults age 12 and older.

For eligible patients, the results of the SCORPIO PEP trial suggest this option may help protect a range of individuals from COVID-19, including those at higher risk for severe illness. During respiratory season, consider discussing it with older adults, people with chronic conditions, and patients who, for whatever reason, are not up to date on vaccination, including those who didn't seem to mount a sufficient response to the vaccine.

Other candidates for the medication could be those who have a harder time managing responsibilities if they do get sick, for example, single parents, caregivers, those who need to avoid illness due to work, school, and travel, those kinds of folks.

So as we summarize the introduction of this new type of post-exposure treatment, what are some key points that might be helpful as family doctors talk with their patients about this? COVID-19 is still something that your family physician should help you navigate.

The virus continues to change, it spreads easily, and it can look like a lot of other respiratory illnesses.

Vaccination remains an important tool, especially because it helps lower the risk of severe illness. But some patients still get sick after exposure, especially since vaccine efficacy wanes after about six months.

If you were recently exposed to COVID-19, there's a new oral medication that might be helpful in preventing you from getting sick and spreading the disease to others in your family or workplace.

This is known as post-exposure prophylaxis or PEP. This medication may be a consideration for patients who are at higher risk of infection or severe disease, such as those with other medical conditions, those who cannot be vaccinated, or are otherwise not current on their vaccination.

Hey, thank you, Dr. Silverberg. Thanks for joining us and sharing more about ensitrelvir.

It's a new COVID-19 PEP medication. It's an option family physicians may want to learn more about to help patients after exposure to COVID-19. And thank you to Shionogi for making today's conversation possible.

To our listeners, the research study is linked in the show notes for easy access. If you'd like more resources related to COVID-19 prevention, including resources from the AAFP, be sure to check out those notes.

If you enjoyed today's episode, let us know by dropping a line to aafpnews@aafp.org​. Be sure to share the episode with your followers on social media and tag the AAFP.