5 Key April FDA Approvals Signal Momentum Across Rare, Chronic Diseases

April brought a wave of regulatory momentum, with 5 notable FDA approvals spanning endocrinology, immunology, infectious disease, and gene therapy. A novel doravirine/islatravir combination (Idvysno; Merck) introduced the first non–integrase strand transfer inhibitor (non-INSTI)–based, tenofovir-free regimen for HIV, broadening treatment flexibility.¹ Teplizumab-mzwv (Tzield; Sanofi) expanded to younger children with stage 2 type 1 diabetes (T1D), marking a milestone as an early disease-modifying option.² Dupilumab (Dupixent; Sanofi and Regeneron) gained approval for young children with chronic spontaneous urticaria (CSU),³ and a first-in-class gene therapy, lunsotogene parvec-cwha (Otarmeni; Regeneron), offers new hope for otoferlin (OTOF) gene-related hearing loss.⁴ Rounding out the month, the weekly anifrolumab-fnia autoinjector (Saphnelo; AstraZeneca) signals progress in simplifying systemic lupus erythematosus (SLE) care.⁵ Together, these decisions underscore continued innovation across both rare and prevalent conditions.

First Non-INSTI, Tenofovir-Free Regimen DOR/ISL Gains FDA Approval for HIV

This fixed-dose, 2-drug combination is a once-daily, single-tablet combination of 100-mg doravirine and 0.25-mg islatravir indicated for adults with virologically suppressed HIV-1 (HIV RNA < 50 copies/mL) with no history of treatment failure or known resistance to doravirine.^1,6 It is intended to replace an existing stable antiretroviral therapy. The approval is notable as the first complete 2-drug regimen that is both non-INSTI–based and tenofovir free, offering a simplified alternative for patients seeking to avoid certain drug classes or reduce treatment burden.

The decision was supported by the phase 3 MK-8591A-052 (trial 052; NCT05630755) and MK-8591A-051 (trial 051; NCT05631093) studies.⁶ In trial 052, which compared switching to doravirine/islatravir vs continuing bictegravir/emtricitabine/tenofovir alafenamide, 1% of patients in both groups had HIV RNA loads of at least 50 copies/mL at week 48, demonstrating noninferiority. Viral suppression rates remained high, with 92% vs 94%, respectively. In trial 051, which evaluated patients switching from various baseline regimens, 1% of those receiving doravirine/islatravir vs 5% of those continuing baseline therapy had viral loads of at least 50 copies/mL. Across both trials, more than 700 participants were included, with adults ranging aged 18 to older than 80 years and safety profiles that were comparable to standard regimens, with low discontinuation rates.

“People aging with HIV face additional health challenges, including managing multiple chronic conditions and medications at the same time,” said Carl Baloney Jr, president and CEO of AIDS United, in a statement. “It is essential that management of HIV considers these factors in addition to virologic suppression when choosing an HIV treatment regimen.”

FDA Expands Teplizumab-mzwv Approval to Young Children With Stage 2 T1D

With its April 22 approval, use of the CD3-directed monoclonal antibody teplizumab-mzwv became indicated for children 1 year and older with stage 2 T1D,² a presymptomatic phase marked by dysglycemia and the presence of diabetes-related autoantibodies.⁷ This approval aims to delay progression to stage 3 T1D, which necessitates lifelong insulin therapy.

The expanded approval—previously, just children 8 years and older were included—was supported by interim findings from the phase 4 PETITE-T1D trial (NCT05757713), which enrolled 23 participants with a mean age of 4.8 years, all of whom received a 14-day course of daily intravenous (IV) teplizumab. Results showed that although all participants experienced treatment-emergent adverse events (AEs), no grade 4 or 5 AEs were reported, and discontinuations were limited to manageable issues such as anemia, elevated liver enzymes, and rash.

Because stage 2 T1D is often asymptomatic, early identification is critical. By enabling treatment in children as young as 1 year, the updated indication allows for earlier immunomodulatory intervention, potentially altering long-term disease trajectory.

“This is especially important because these children are often at the highest risk of progressing quickly and without warning,” said Kimber Simmons, MD, MS, associate professor of pediatrics, Barbara Davis Center. “Delaying the onset of stage 3 type 1 diabetes during the years when management is often most difficult because of a child’s small size and dependence on caregivers could have a truly meaningful impact for families.”

FDA Approves Dupilumab for Young Children With Uncontrolled CSU

Dupilumab was approved for CSU in children aged 2 to 11 years who remain symptomatic despite histamine-1 antihistamine therapy.³ The chronic inflammatory skin disease is characterized by recurrent hives and severe itching driven in part by type 2 inflammation. This decision made dupilumab the first biologic therapy approved for this pediatric population, addressing a significant unmet need among more than 14,000 affected children in the US with uncontrolled disease.

Data from the LIBERTY-CUPID phase 3 clinical trial program, which included Studies A and C (NCT04180488) and Study B (NCT04180488), and the CUPIDKids trial (NCT05526521), supported the approval. Evidence from these trials demonstrated that dupilumab significantly reduced itch severity and overall disease activity, as measured by the weekly Urticaria Activity Score (UAS7), compared with placebo at 24 weeks. It also improved rates of well-controlled disease (UAS7 ≤ 6) and complete response (UAS7 = 0) vs placebo.

Safety findings were consistent with dupilumab’s established profile across indications, with injection-site reactions being the most common AE and no new safety signals.

“Until now, these patients had to rely on limited treatment options that didn’t address potential critical mediators of chronic spontaneous urticaria,” expressed Alyssa Johnsen, MD, PhD, global therapeutic area head of immunology development at Sanofi.⁸ “Dupixent is the first biologic approved for patients as young as 2 years of age, offering a targeted approach that inhibits IL-4 and IL-13 signaling, 2 key and central drivers of the type 2 inflammation that contributes to this disease.”

Lunsotogene Parvec Becomes First FDA-Approved Gene Therapy for OTOF-Related Hearing Loss

This accelerated approval made lunsotogene parvec the first and only approved in vivo gene therapy for genetic hearing loss caused by mutations in the OTOF gene.⁴ The therapy is indicated for pediatric and adult patients with severe to profound or profound sensorineural hearing loss (greater than 90 dB hearing level [HL]) who have molecularly confirmed biallelic OTOF variants, preserved outer hair cell function, and no prior cochlear implant in the treated ear. It has a 1-time administration by adeno-associated virus–based gene delivery via intracochlear infusion.

Approval was supported by results from the pivotal, open-label, multicenter phase 1/2 CHORD trial (NCT05788536), which enrolled infants, children, and adolescents with OTOF-related hearing loss. At 24 weeks, 80% of evaluable participants met or exceeded the primary end point: achieve an average hearing threshold of 70 dB HL or less on behavioral pure-tone audiometry, a level associated with functional acoustic hearing. Longer-term follow-up demonstrated that 42% of participants achieved normal hearing, including the ability to detect whisper-level sounds.

Lunsotogene parvec is also the first gene therapy approved under the FDA Commissioner’s National Priority Voucher program, and it represents a major advance for a condition that previously lacked disease-modifying treatments, as OTOF-related hearing loss has historically been managed with assistive devices.

“The 1-time gene therapy demonstrated rapid, meaningful and consistent hearing responses, with most children achieving remarkable hearing improvements,” said A. Eliot Shearer, MD, PhD, otolaryngologist, Boston Children’s Hospital, and a CHORD trial investigator, in a statement.⁹ “I’ve witnessed firsthand my trial participant responding to their mother’s voice, dancing to music, and interacting with the world, and these moments are now possible for more children born with this specific form of hearing loss.”

FDA Approves First-in-Class Weekly Anifrolumab Autoinjector for Systemic Lupus Erythematosus

With this approval, the FDA introduced a first-in-class, once-weekly subcutaneous (SC) autoinjector for adult patients with SLE receiving standard therapy, meaning this group now has access to a more convenient, self-administered alternative to the previously available IV infusion in use since 2021.⁵ The decision was supported by results from the phase 3 TULIP-SC trial (NCT04877691), a randomized, double-blind, placebo-controlled study evaluating SC anifrolumab in 367 adults aged 18 to 70 years with moderate to severe autoantibody-positive SLE.

Patients received weekly 120-mg injections or placebo alongside background therapies such as corticosteroids, antimalarials, and immunosuppressants. The primary end point—disease activity reduction at week 52 measured by the British Isles Lupus Assessment Group–based Composite Lupus Assessment—was met, with significantly more patients achieving a response in the anifrolumab arm vs the placebo arm. Additional findings showed clinically meaningful improvements, including faster responses and delayed time to flare.

Exploratory outcomes further supported efficacy, with 29.0% of patients achieving Definitions of Remission in SLE–defined remission and 40.1% reaching low disease activity via the Low-Level Disease Activity Score. The safety profile of the SC formulation was consistent with the IV version, with no new safety signals identified.

Anifrolumab is a fully human monoclonal antibody that targets the type I interferon receptor (IFNAR1), blocking inflammatory signaling pathways central to SLE pathogenesis.

“The FDA approval of a subcutaneous administration option for anifrolumab is an exciting milestone for the lupus community,” said Louise Vetter, president and CEO, Lupus Foundation of America, in a statement, “because it offers people with [SLE] more convenience and choice of where and how they want to receive treatment.”¹⁰

References

1. Grossi G. First non-INSTI, tenofovir-free regimen DOR/ISL fains FDA approval for HIV. AJMC^®. April 22, 2026. Accessed May 4, 2026. https://www.ajmc.com/view/first-non-insti-tenofovir-free-regimen-dor-isl-gains-fda-approval-for-hiv
2. Steinzor P. FDA expands teplizumab-mzwv approval to young children with stage 2 T1D. AJMC. April 22, 2026. Accessed May 4, 2026. https://www.ajmc.com/view/fda-expands-teplizumab-mzwv-approval-to-young-children-with-stage-2-t1d
3. McNulty R. FDA approves dupilumab for young children with uncontrolled CSU. AJMC. April 23, 2026. Accessed May 4, 2026. https://www.ajmc.com/view/fda-approves-dupilumab-for-young-children-with-uncontrolled-csu
4. McNulty R. Lunsotogene parvec becomes first FDA-approved gene therapy for OTOF-related hearing loss. AJMC. April 23, 2026. Accessed May 4, 2026. https://www.ajmc.com/view/lunsotogene-parvec-becomes-first-fda-approved-gene-therapy-for-otof-related-hearing-loss
5. McCormick B. FDA approves first-in-class weekly anifrolumab autoinjector for systemic lupus erythematosus. AJMC. April 27, 2026. Accessed May 4, 2026. https://www.ajmc.com/view/fda-approves-first-in-class-weekly-anifrolumab-autoinjector-for-systemic-lupus-erythematosus
6. FDA approves Merck’s once-daily Idvynso (doravirine/islatravir) for adults with virologically suppressed HIV-1. News release. Merck & Co. April 21, 2026. Accessed May 4, 2026. https://www.merck.com/news/fda-approves-mercks-once-daily-idvynso-doravirine-islatravir/
7. Sanofi’s Tzield approved in the US to delay the onset of stage 3 type 1 diabetes in young children. News release. Sanofi. April 22, 2026. Accessed May 4, 2026. https://www.sanofi.com/en/media-room/press-releases/2026/2026-04-22-05-05-00-3278650
8. Sanofi and Regeneron’s Dupixent approved in the US as the first biologic medicine for young children with uncontrolled chronic spontaneous urticaria. News release. Sanofi. April 22, 2026. Accessed May 4, 2026. https://www.news.sanofi.us/2026-04-22-Sanofi-and-Regenerons-Dupixent-approved-in-the-US-as-the-first-biologic-medicine-for-young-children-with-uncontrolled-chronic-spontaneous-urticaria
9. Otarmeni (lunsotogene parvec-cwha) approved by FDA as first and only gene therapy for genetic hearing loss; Regeneron to provide Otarmeni for free in the U.S. News release. Regeneron. April 23, 2026. Accessed May 4, 2026. https://investor.regeneron.com/news-releases/news-release-details/otarmenitm-lunsotogene-parvec-cwha-approved-fda-first-and-only
10. Saphnelo approved in the US for subcutaneous self-administration as a new autoinjector for the treatment of systemic lupus erythematosus. News release. AstraZeneca. April 27, 2026. Accessed May 4, 2026. https://www.astrazeneca-us.com/media/press-releases/2026/SAPHNELO-approved-in-the-US-for-subcutaneous-self-administration-as-a-new-autoinjector-for-the-treatment-of-systemic-lupus-erythematosus.html