Molnupiravir vs. Other COVID-19 Antivirals: What Works Best in 2025

When COVID-19 hit, we scrambled for treatments. Now, in 2025, we have real options - but not all are created equal. If you’re wondering whether Molnupiravir is still the best choice, or if something else works better, you’re not alone. Millions of people have asked the same question. The answer isn’t simple, but it’s clear once you know the facts.

What is Molnupiravir?

Molnupiravir is an oral antiviral drug developed to treat mild to moderate COVID-19 in adults at high risk for severe illness. Also known as Lagevrio, it was first authorized by the FDA in December 2021. It works by introducing errors into the virus’s genetic code, making it impossible for SARS-CoV-2 to replicate properly.

It’s taken as four capsules twice a day for five days. That’s it - no IV, no clinic visits. That convenience made it popular early on. But effectiveness? That’s where things get messy.

Early trials showed a 30% reduction in hospitalization or death among high-risk patients. But later real-world data from the UK and the U.S. showed much lower numbers - closer to 10-15%. That’s not nothing, but it’s far from a miracle. And there’s a catch: it’s not recommended for pregnant people because of potential harm to fetal DNA. It’s also not used in kids under 18.

Paxlovid: The Gold Standard

Paxlovid is a combination antiviral pill containing nirmatrelvir and ritonavir, approved by the FDA in December 2021. It’s widely considered the most effective oral treatment for early-stage COVID-19.

In clinical trials, Paxlovid cut hospitalizations and deaths by nearly 90% in high-risk adults. Real-world studies from 2023 to 2025 confirm it still holds up - even against newer variants like JN.1 and KP.2. It’s taken as three pills twice a day for five days.

But Paxlovid has downsides. It interacts with a ton of common medications - statins, blood thinners, some antidepressants, even certain heart meds. If you’re on multiple prescriptions, your doctor might skip Paxlovid entirely. Also, some people get what’s called “Paxlovid rebound”: symptoms return after finishing the course. It’s not dangerous, but it’s unsettling.

Still, for most eligible adults - especially those over 65, with diabetes, heart disease, or weakened immune systems - Paxlovid remains the top pick.

Remdesivir: The IV Option

Remdesivir is an intravenous antiviral originally developed for Ebola, later repurposed for COVID-19. It’s sold under the brand name Veklury and has been used since May 2020.

Unlike Molnupiravir and Paxlovid, Remdesivir requires a hospital or infusion center visit. You get it through an IV over three days. That makes it less convenient - but it’s still used for people who can’t take oral meds, or when Paxlovid isn’t an option due to drug interactions.

Studies show it reduces hospital stays by about 3-4 days in moderate cases. But it doesn’t lower death rates as clearly as Paxlovid. It’s also expensive - over $3,000 per course in the U.S. without insurance.

Remdesivir is often used in older adults with kidney problems who can’t take Paxlovid, or in patients who show signs of worsening symptoms but aren’t yet hospitalized.

Ensitrelvir: The Newcomer

Ensitrelvir is a newer oral antiviral developed in Japan and approved in late 2023. It’s not yet available in the U.S. or Europe, but it’s gaining attention.

Early data shows it reduces viral load faster than Molnupiravir and may lower symptom duration by nearly two days. It also has fewer drug interactions than Paxlovid. That’s a big deal.

But here’s the catch: it’s not approved by the FDA. The U.S. hasn’t even started the review process. So if you’re in America, you can’t get it. In Japan and South Korea, it’s already being prescribed. If you’re traveling or have access to international pharmacies, you might find it - but tread carefully. Counterfeit versions are popping up.

How Do They Stack Up?

Here’s how the top three compare in 2025:

One thing stands out: Paxlovid is still the most effective. But if you’re on blood pressure meds, cholesterol drugs, or antidepressants, your doctor might avoid it. That’s where Molnupiravir comes in - it’s the fallback. Not the best, but the safest when other options are off the table.

Who Should Take What?

There’s no one-size-fits-all. Your best choice depends on your health, meds, and risk level.

• If you’re over 65, have diabetes, heart disease, or are immunocompromised - Paxlovid is your first choice, unless you’re on conflicting meds.
• If you’re on statins, blood thinners, or certain antidepressants - Molnupiravir is the safer oral option, even if it’s less effective.
• If you’re hospitalized or can’t swallow pills - Remdesivir is the go-to.
• If you’re under 18, pregnant, or breastfeeding - none of these are ideal. Talk to your doctor about monoclonal antibodies or other supportive care.

Timing matters too. All these drugs work best when taken within five days of symptom onset. Waiting until day six? The benefit drops sharply. Don’t delay.

Why Molnupiravir Still Has a Role

Even with Paxlovid’s superiority, Molnupiravir isn’t obsolete. It’s still used in about 1 in 5 cases in the U.S. Why?

• It’s cheaper - around $300 per course vs. $500+ for Paxlovid.
• It doesn’t interfere with most prescriptions.
• It’s easier to stockpile in pharmacies and rural clinics.
• Some people simply can’t get Paxlovid because of interactions.

It’s not the star - but it’s the reliable backup. Think of it like a spare tire. You hope you never need it, but you’re glad it’s there.

What’s Coming Next?

Researchers are working on next-gen antivirals. One called EDP-235 is in Phase 3 trials and shows promise with fewer side effects and no drug interactions. Another, BTA-C11, targets a different part of the virus and might work even if mutations arise.

But in 2025, we’re still working with what we have. The CDC still recommends Paxlovid as first-line for eligible patients. Molnupiravir? It’s second-tier - but still a valid option when the first choice isn’t possible.

Bottom Line

Molnupiravir isn’t the best antiviral for COVID-19 anymore. Paxlovid is. But that doesn’t mean Molnupiravir is useless. It’s a practical, accessible tool when Paxlovid isn’t an option. If you’re high-risk and get infected, call your doctor right away. Don’t wait. Don’t assume you know what’s best. The right drug depends on your body, your meds, and your risk - not on headlines or social media posts.

And remember: antivirals aren’t magic. They work best with rest, hydration, and early treatment. If you’re feeling worse after day three, get checked. No pill replaces a doctor’s judgment.

What to Do Next

If you’re at high risk for severe COVID-19, talk to your doctor now - not when you’re sick. Ask: “If I test positive, what’s my best treatment option?” Get a plan. Know what pills you can and can’t take. Keep a list of your medications handy.

Don’t wait until you’re coughing and feverish to figure it out. The window to start antivirals is small - five days max. By then, it’s too late if you didn’t plan ahead.