Idvynso

Idvynso is used to treat HIV-1 in adults, as a complete treatment regimen to replace their current antiretroviral regimen in those who are virologically suppressed (HIV-1 RNA <50 copies per mL) on a stable antiretroviral regimen with no history of virologic treatment failure and no known substitutions associated with resistance to doravirine. It is a two-drug combination tablet containing doravirine 100 mg and islatravir 0.25 mg that is taken once a day.

Idvynso is the first non-INSTI, tenofovir-free, once-daily, two-drug regimen to demonstrate non-inferior efficacy to bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) or baseline antiretroviral therapy in Phase 3 clinical trials. In Trial 052 (NCT05630755), 92% of participants switched to Idvynso maintained viral suppression at Week 48, versus 94% on BIC/FTC/TAF. In Trial 051 (NCT05631093), 96% on Idvynso maintained suppression versus 92% on background antiretroviral therapy. Outcomes were consistent across subgroups by age, sex, and race.

Idvynso (doravirine/islatravir) gained FDA approval on April 20, 2026. There is no generic.

Take 1 Idvynso tablet every day. Try to take it at the same time each day.

• Idvynso may be taken with or without food.
• Do NOT miss or skip doses as this can cause resistance to Idvynso.
• If you forget to take Idvynso, take the missed dose right away, unless it is almost time for the next dose. Do not double up on doses.

Idvynso may cause severe skin reactions:

• Skin and Hypersensitivity Reactions. Severe skin reactions, including Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) and Drug Rash with Eosinophilia and Systemic Symptoms (DRESS), have been reported with doravirine-containing regimens. Contact your healthcare provider immediately if you develop a rash. Stop taking Idvynso and see a doctor right away if you develop a painful rash that affects your mouth, eyes, or genitals, or a rash accompanied by symptoms like fever, fatigue, or body aches.

Do not take Idvynso if you are taking certain medications such as strong cytochrome P450 (CYP)3A enzyme inducers, or lamivudine (3TC) or emtricitabine (FTC). Co-administration with these drugs may decrease the effectiveness of Idvynso.

Before taking Idvynso, tell your healthcare provider about all your health conditions, including if you:

• Are taking any medications that may interact with Idvynso, including prescription drugs, over-the-counter medicines, or herbal supplements, especially St. John's Wort, rifabutin, lamivudine (3TC) or emtricitabine (FTC)
• Have ever had a skin reaction or rash from an HIV medication
• Have a history of virologic treatment failure or known resistance to doravirine
• Are allergic to Idvynso, doravirine, islatravir, or any of the ingredients in the tablets
• Are pregnant or planning to become pregnant
• Are breastfeeding or planning to breastfeed.

Pregnancy Registry

There is an antiretroviral pregnancy registry to monitor fetal outcomes in pregnant women exposed to Idvynso. Healthcare providers are encouraged to register patients by calling the Antiretroviral Pregnancy Registry (APR) at 1-800-258-4263.

Breastfeeding

Breastfeeding is not recommended when you have HIV-1 because of potential risks, which include:

• HIV-1 transmission (in infants without HIV-1)
• Development of viral resistance (in infants with HIV-1)
• Serious side effects in a breastfed infant, similar to those seen in adults.

The most common side effects of Idvynso are:

• Diarrrhea
• Dizziness
• Fatigue
• Bloating
• Heading
• Weight gain.

See the Idvynso Prescribing Information for a full list of side effects. To report suspected adverse reactions, contact Merck Sharp & Dohme LLC at 1-877-888-4231 or the FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Dose of Idvynso for HIV-1 treatment

• 1 tablet orally once a day.

Idvynso combines two medications, doravirine and islatravir, that work together but in different ways to stop HIV-1 from copying itself in the body. Doravirine is a pyridinone non-nucleoside reverse transcriptase inhibitor of HIV-1 that directly blocks the enzyme HIV needs to replicate, called HIV-1 reverse transcriptase (RT).

Islatravir is a deoxyadenosine nucleoside analog reverse transcriptase inhibitor that gets converted inside cells into its active form, islatravir-triphosphate, which blocks translocation and induces structural changes in viral DNA that prevent further nucleotide incorporation. This interrupts and stops the HIV-1 replication process.

Idvynso may interact with certain other drugs. Tell your healthcare provider about all your prescription or nonprescription medications or herbal products. Especially tell your healthcare provider if you take:

• St. John’s wort, strong cytochrome P450 (CYP)3A enzyme inducers, such as phenytoin, carbamazepine, or phenobarbital; lamivudine (3TC) or emtricitabine (FTC). These should not be taken with Idvynso
• Rifabutin. Talk to your healthcare provider about taking an extra tablet of doravirine (PIFELTRO) 100 mg approximately 12 hours after the dose of Idvynso.

This is not a complete list of interactions. See the Idvynso Prescribing Information for a complete list.

Keep Idvynso at room temperature in its original, tightly closed. Do not remove the desiccant packet inside. Avoid storing in humid areas like bathrooms.

Idvynso is manufactured for Merck Sharp & Dohme LLC, Rahway, NJ 07065, USA.

Active ingredients: doravirine 100 mg and islatravir 0.25 mg

Inactive ingredients: colloidal silicon dioxide, croscarmellose sodium, hypromellose acetate succinate, lactose monohydrate, magnesium stearate, and microcrystalline cellulose.

Film coating: calcium carbonate, ferric oxide, ferrosoferric oxide, hypromellose, lactose monohydrate, and triacetin. Polished with carnauba wax.

Available as oral tablets containing 100 mg doravirine and 0.25 mg islatravir.