---
title: "Gilead, Merck weekly HIV pill keeps virus suppressed in late-stage trials"
type: "News"
locale: "en"
url: "https://longbridge.com/en/news/293371056.md"
datetime: "2026-07-21T17:22:38.000Z"
locales:
  - [zh-CN](https://longbridge.com/zh-CN/news/293371056.md)
  - [en](https://longbridge.com/en/news/293371056.md)
  - [zh-HK](https://longbridge.com/zh-HK/news/293371056.md)
---

# Gilead, Merck weekly HIV pill keeps virus suppressed in late-stage trials

July 21 (Reuters) - Gilead Sciences (GILD.O) and Merck (MRK.N) said on Tuesday their experimental once-weekly HIV pill kept the virus suppressed in two late-stage trials, supporting regulatory filings for what could become the first regimen of its kind for the disease.

Here are some details:

-   The combination of Merck’s islatravir and Gilead’s lenacapavir was tested as a single-tablet regimen in adults whose HIV was already controlled with daily antiretroviral therapy.
-   HIV attacks the body’s immune system and, if left untreated, can progress to acquired immunodeficiency syndrome (AIDS), the most advanced stage of infection.
-   In one trial, none of the patients who switched to the weekly pill had detectable viral levels at 48 weeks, compared with 0.3% of those who remained on Gilead’s daily Biktarvy.
-   In a second trial, 0.3% of patients taking the weekly pill had detectable HIV levels or higher at 48 weeks, compared with 1.3% of those who remained on standard daily HIV regimens.
-   Investors are closely watching the rollout of lenacapavir, branded as Yeztugo, which was approved last year, as Gilead seeks to strengthen its HIV franchise alongside blockbuster treatment Biktarvy.
-   The companies said the weekly treatment was non-inferior to Biktarvy and other daily HIV regimens in the two studies, meaning it performed at least as well by the studies’ main measure.
-   Side effects were generally similar to the daily treatments studied, and no new safety concerns were identified. The most common treatment-related side effects included headache, nausea and diarrhea.
-   Merck’s once-daily HIV pill combo Idvynso was approved by the U.S. Food and Drug Administration in April, bringing another treatment option for patients suffering from the condition.

### Related Stocks

- [GIS.DE](https://longbridge.com/en/quote/GIS.DE.md)
- [MRK.US](https://longbridge.com/en/quote/MRK.US.md)
- [GILD.US](https://longbridge.com/en/quote/GILD.US.md)

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