Phase 3 Clinical Trial Reporting, Prospective Regulatory Filings to Watch For in 2026

This year will bring about the reporting of data for clinical trials, launch of studies, and the FDA approvals of therapeutics and vaccines.

Listed below are some therapeutics and vaccines that are in planning to go into phase 3 clinical trials, will be reporting data on existing phase 3 trials, or looking to file their data with regulatory agencies in order to seek approval. It is important to note, this is not a comprehensive list and more updates will be provided as more companies report on their products.

Lyme Disease

The Pfizer and Valneva vaccine candidate, VLA15, is in phase 3 trial and followed participants for the occurrence of disease until the end of the Lyme disease season last year. This study is part of their Vaccine Against Lyme for Outdoor Recreationists (VALOR) trial. The trial is a multicenter, placebo-controlled, randomized, observer-blinded trial conducted at sites in areas where Lyme disease is highly endemic across the US, Canada, and Europe. The aim of the trial was to evaluate the efficacy, safety, tolerability, immunogenicity, and lot consistency of VLA15, a 6-valent OspA-based Lyme disease vaccine candidate.¹ Trial participants aged 5 years and older were randomized 1:1 into two trial groups and receive four doses of either VLA15 or a saline placebo – one dose each at months 0, 2, 5-9 and a booster one year after the third dose, shortly before the peak of the next Lyme disease season.¹ Data is expected to be reported this year.

Hepatitis C

Late last year, Atea Pharmaceuticals reported modeling data indicating that its investigational combination of bemnifosbuvir (BEM) and ruzasvir (RZR) may deliver near-complete suppression of hepatitis C virus (HCV) activity, with a predicted time to cure of approximately 7 to 8 weeks.² The first phase 3 HCV topline results are expected this year. “Across our antiviral pipeline, we continue to execute with discipline and urgency and are on track for the first Phase 3 HCV topline results in mid-2026,” Jean-Pierre Sommadossi, PhD, Chief Executive Officer and Founder of Atea, said in a statement.

Carbapenem-Resistant Acinetobacter baumannii (CRAB) Infections

Last year, pharmaceutical company, Roche, says it planned to launch a phase 3 trial of its novel antibiotic candidate, zosurabalpin, in patients with CRAB infections. Roche says the trial is expected to launch in early 2026. To learn more about the investigational antimicrobial, go here.

HIV

Back in December, Gilead Sciences announced positive topline results from its phase 3 ARTISTRY-2 trial evaluating an investigational fixed-dose combination of bictegravir 75 mg and lenacapavir 50 mg (BIC/LEN) in adults with HIV who were virologically suppressed on bictegravir 50 mg/emtricitabine 200 mg/tenofovir alafenamide 25 mg tablets (B/F/TAF; Biktarvy). During the announcement of their data release, the company mentioned their plans to file their data to regulatory agencies in order to seek approval.

“These data support the potential of BIC/LEN as a meaningful additional treatment option for adults with HIV who are virologically suppressed. We look forward to sharing the full phase 3 data from the ARTISTRY-1 and ARTISTRY-2 trials next year and submitting these data for regulatory approval,” Jared Baeten, MD, PhD, senior vice president of clinical development and virology at Gilead, said in a statement.³

References

1.Phase 3 VALOR Lyme Disease Trial: Valneva and Pfizer Announce Primary Vaccination Series Completion. Valneva press release. July 17, 2024. Accessed January 13, 2026.
https://valneva.com/press-release/phase-3-valor-lyme-disease-trial-valneva-and-pfizer-announce-primary-vaccination-series-completion/

2. Atea Pharmaceuticals Presents New Data Supporting the Fixed-Dose Combination of Bemnifosbuvir and Ruzasvir as a Potential Best-in-Class Regimen for Treatment of Hepatitis C Virus Infection at The Liver Meeting® 2025.November 7, 2025. Accessed November 24, 2025.
https://ir.ateapharma.com/news-releases/news-release-details/atea-pharmaceuticals-presents-new-data-supporting-fixed-dose

3. Gilead’s Investigational Single-Tablet Regimen of Bictegravir and Lenacapavir for HIV Treatment Meets Primary Endpoint in Phase 3 ARTISTRY-2 Trial. Gilead Sciences Press release. December 15, 2025. Accessed December 15, 2025.
https://www.businesswire.com/news/home/20251215879862/en/Gileads-Investigational-Single-Tablet-Regimen-of-Bictegravir-and-Lenacapavir-for-HIV-Treatment-Meets-Primary-Endpoint-in-Phase-3-ARTISTRY-2-Trial