5 Best Weight Loss Drug Stocks to Buy in 2026

3. Merck & Co., Inc. (NYSE:MRK)

Number of Hedge Fund Holders: 98

Merck & Co., Inc. (NYSE:MRK) is one of the best weight loss drugs on this list.

TheFly reported on June 18 that MRK announced that the U.S. Food and Drug Administration (FDA) granted an expanded approval for Capvaxive, extending its use to children and adolescents between 2 and 17 years old. The updated indication applies to pediatric patients who have completed their initial pneumococcal vaccination series and have chronic health conditions that increase their vulnerability to pneumococcal disease. With this authorization, Capvaxive becomes the only pneumococcal conjugate vaccine (PCV) in the United States specifically evaluated and approved for this patient group.

In another major operational breakthrough, on June 12, Merck & Co., Inc. (NYSE:MRK) announced that the U.S. Food and Drug Administration (FDA) approved KEYTRUDA and KEYTRUDA QLEX, its anti-PD-1 therapies, in combination with WELIREG for the adjuvant treatment of adults with clear cell renal cell carcinoma (ccRCC) at an increased risk of recurrence after surgery. The approval marks the first use of WELIREG in earlier-stage ccRCC and the first authorization of a PD-1 and HIF-2α inhibitor combination therapy. The decision was supported by results from the Phase 3 LITESPARK-022 trial, which showed the combination reduced the risk of recurrence, metastasis, or death by 28% compared with KEYTRUDA plus placebo in eligible patients.

Merck & Co., Inc. (NYSE:MRK) is a global healthcare company expanding its obesity pipeline through early-stage GLP-1 and dual agonist therapies. While it lacks a marketed weight-loss drug, its metabolic research and strong pharmaceutical portfolio make it a potential long-term obesity market contender.