Vanda Pharmaceuticals Announces Positive Results from Study 3601 of NEREUS™ (tradipitant) for Prevention of GLP-1-Induced Vomiting

NEREUS™ cut vomiting rates by up to 81% in Phase III GLP-1 therapy trial.

What the company is saying

Vanda Pharmaceuticals is highlighting statistically significant Phase III results for NEREUS™ (tradipitant) in preventing vomiting associated with GLP-1 receptor agonist therapy. The company emphasizes reductions in any vomiting (43.0% vs 58.5% placebo, 27% relative reduction), vomiting plus severe nausea (33.1% vs 50.6%, 35% reduction), frequent multi-day vomiting (6.3% vs 15.9%, 60% reduction), and extreme vomiting (2.8% vs 14.6%, 81% reduction). Vanda frames these results as addressing a major cause of GLP-1 therapy discontinuation, citing that roughly half of patients stop GLP-1 therapy within a year due to gastrointestinal side effects. The company stresses the $50 billion global GLP-1 receptor agonist market as a major commercial opportunity. Vanda states that NEREUS™ was well tolerated with no new safety signals and plans to discuss these results with the FDA, aiming to file a supplemental New Drug Application for this new indication. Dr. Mihael H. Polymeropoulos, President, CEO, and Chairman, is quoted to reinforce the clinical and commercial relevance of the findings.

What the data suggests

The Phase III trial (Study 3601) enrolled 142 participants on NEREUS™ and 164 on placebo, all receiving a single 1 mg dose of semaglutide without titration to maximize the vomiting challenge. NEREUS™ reduced the incidence of any vomiting to 43.0% versus 58.5% on placebo (p=0.006), a 27% relative reduction. The key secondary endpoint—vomiting plus severe nausea—was 33.1% with NEREUS™ versus 50.6% on placebo (p=0.002), a 35% reduction. Frequent multi-day vomiting occurred in 6.3% of NEREUS™ patients versus 15.9% on placebo (p=0.008), a 60% reduction. Extreme vomiting (>10 episodes) was seen in 2.8% of NEREUS™ patients versus 14.6% on placebo (p=0.0003), an 81% reduction. These effects were most pronounced in the first two days after dosing. Safety data show no new signals and consistency with prior studies. The pooled exposure–response analysis suggests stable efficacy across semaglutide concentrations, supporting real-world applicability. The $50 billion market size is cited, but no revenue, profit, or cost data for Vanda are disclosed. The evidence strongly supports efficacy for this indication, but commercial and regulatory outcomes are not yet realized.

Analysis

The announcement presents robust, statistically significant Phase III clinical trial results for NEREUS™ in preventing vomiting associated with GLP-1 receptor agonist therapy, with clear numerical data supporting efficacy and safety. However, the narrative inflates the immediate investment case by emphasizing the large ($50 billion) GLP-1 market and the potential applicability of NEREUS™ across all GLP-1 therapies, despite no regulatory approval for this indication yet. The most material forward-looking claims—FDA discussions and a planned sNDA—are not yet realized, and there is no disclosure of revenue, profit, or cash flow impact. The benefits to Vanda are long-term, contingent on regulatory approval and subsequent commercial uptake. The language around market size and broad applicability is aspirational, not yet substantiated by regulatory or commercial milestones. No large capital outlay is disclosed, so capital intensity is not a concern here.

Risk flags

• ●Regulatory approval risk is high: Vanda has not yet submitted the sNDA, and FDA acceptance, review, and approval are uncertain. The timeline to a commercial launch for this indication could be extended if the FDA requests additional data or raises concerns.
• ●Commercial uptake risk: While the GLP-1 receptor agonist market exceeds $50 billion, there is no evidence yet of NEREUS™ market penetration or payer acceptance for this indication. Real-world adoption may lag if prescribers or insurers are slow to recognize or reimburse for the new use.
• ●Data generalizability risk: The trial used a single 1 mg semaglutide dose without titration, which may not fully reflect typical clinical practice. Although the company claims efficacy is stable across exposures, real-world patient populations and dosing regimens could yield different results.
• ●Competitive and market risk: Multiple approaches to managing GLP-1-induced nausea and vomiting exist, and future entrants or generic competition could limit the commercial opportunity even if approval is secured.
• ●Forward-looking claims risk: The announcement emphasizes broad applicability and market size, but these outcomes depend on successful regulatory, commercial, and clinical execution, none of which are guaranteed at this stage.

Bottom line

Vanda's Phase III data for NEREUS™ show robust, statistically significant reductions in vomiting and severe nausea for patients on GLP-1 receptor agonist therapy, with up to 81% relative reduction in extreme vomiting. The safety profile is consistent with prior studies, and the company is targeting a large, expanding $50 billion market. However, the path to value realization depends on FDA approval of a supplemental New Drug Application, which has not yet been submitted. There are execution risks around regulatory acceptance, real-world adoption, and payer reimbursement, and the trial design may not fully mirror clinical practice. The most important takeaway is that while the clinical efficacy is clear, investors will need to watch for regulatory milestones and early commercial traction before the opportunity can be fully quantified.

Announcement summary

(NASDAQ:VNDA) Vanda Pharmaceuticals Inc. announced positive results from Study 3601 (VP-VLY-686-3601), a Phase III randomized, placebo-controlled study evaluating NEREUS™ (tradipitant), an oral neurokinin-1 (NK-1) receptor antagonist, for the prevention of vomiting associated with GLP-1 receptor agonist therapy. The primary endpoint showed that any vomiting occurred in 43.0% (61/142) of NEREUS™-treated participants compared to 58.5% (96/164) on placebo (p=0.006), representing a 27% relative reduction. The key secondary endpoint, defined as any vomiting together with worst nausea ≥3, occurred in 33.1% (47/142) of NEREUS™ participants versus 50.6% (83/164) on placebo (p=0.002), a 35% relative reduction. Exploratory analyses found that frequent multi-day vomiting (>2 episodes on more than one day) occurred in 6.3% (9/142) of NEREUS™ participants versus 15.9% (26/164) on placebo (p=0.008), a 60% relative reduction. Extreme vomiting (>10 total episodes) was observed in 2.8% (4/142) of NEREUS™ participants compared to 14.6% (24/164) on placebo (p=0.0003), corresponding to an 81% relative reduction. The study design involved a single 1 mg dose of semaglutide without gradual titration, providing a rigorous test of prevention under strong emetogenic stimulus. A pooled exposure–response analysis of Phase II and III data showed the reduction in vomiting probability with NEREUS™ remained stable across the observed semaglutide concentration range. NEREUS™ is an NK-1 receptor antagonist that acts at the vomiting center, including the area postrema (AP) and nucleus tractus solitarius (NTS), and is expected to be applicable across all available GLP-1 receptor agonist therapies. Nausea and vomiting are among the most common reasons patients discontinue or fail to reach therapeutic doses of GLP-1 receptor agonists, with real-world studies showing roughly half of patients discontinue GLP-1 therapy within one year due to gastrointestinal side effects. The global GLP-1 receptor agonist market exceeds $50 billion and continues to expand. NEREUS™ was generally well tolerated, with a safety profile consistent with previous studies and no new safety signals observed. Vanda intends to discuss the results with the U.S. Food and Drug Administration (FDA) and is planning a supplemental New Drug Application (sNDA) to support the use of NEREUS™ for the prevention of vomiting associated with GLP-1 receptor agonist therapy. Dr. Mihael H. Polymeropoulos, President, CEO and Chairman of the Board of Vanda, stated that the results demonstrate NEREUS™ can meaningfully reduce vomiting and frequent multi-day vomiting induced by GLP-1 therapy, which are key contributors to treatment discontinuation. NEREUS™ (tradipitant) is already approved as of December 2025 for the prevention of motion-induced vomiting.

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