Last reviewed 2026-04-20 · How we verify

Zynrelef

Zynrelef is a marketed drug developed by Texas Tech University Health Sciences Center, currently holding a position in the pain management market. The key composition patent for Zynrelef is set to expire in 2028, providing a period of exclusivity that supports its market presence. The primary risk facing Zynrelef is the potential increase in competition following the patent expiry in 2028.

At a glance

Approved indications

No approved indications tracked.

Boxed warnings

• WARNING: RISK OF SERIOUS CARDIOVASCULAR AND GASTROINTESTINAL EVENTS WARNING: RISK OF SERIOUS CARDIOVASCULAR AND GASTROINTESTINAL EVENTS See full prescribing information for complete boxed warning. Nonsteroidal anti-inflammatory drugs (NSAIDs) cause an increased risk of serious cardiovascular thrombotic events, including myocardial infarction and stroke, which can be fatal. This risk may occur early in treatment and may increase with duration of use ( 5.1 ) ZYNRELEF is contraindicated in the sett

Common side effects

• Vomiting
• Constipation
• Headache
• Pruritus
• Postoperative anemia

Serious adverse events

• Peptic ulcer hemorrhage
• Gastritis requiring hospitalization
• Hematemesis
• Melena
• Gastrointestinal hemorrhage
• Increased hepatic enzymes

Key clinical trials

• Post-Operative Pain Relief: Zynrelef or Periarticular Injections in RATKA (PHASE4)
• ZYNRELEF vs Continuous Catheter for Pain Management Following Shoulder Arthroplasty (PHASE4)
• Zynrelef Versus Adductor Canal Block (PHASE4)
• Periarticular Bupivacaine + Meloxicam ER Solution Versus Standard Practice During Total Knee Arthroplasty (PHASE4)
• ZYNRELEF for Pain Management in Total Knee Arthroplasty (PHASE4)
• Zynrelef vs Exparel: The Battle of Postoperative Pain Control After Robotic Sleeve Gastrectomy (EARLY_PHASE1)
• A Multi-surgery Assessment of ZYNRELEF (HTX-011), AMAZE. (PHASE4)
• A Multi-surgery Assessment of ZYNRELEF (HTX-011), AMAZE (PHASE4)

Primary sources

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