Pacira Ends Hip Osteoarthritis Injection Study for ZILRETTA: What Investors Should Know

Pacira (PCRX) announced an update on their ongoing clinical study.

Study Overview: Pacira Pharmaceuticals is running a Phase 2 trial titled “A Phase 2, Randomized, Open-Label, Two-Arm Study to Evaluate a Procedure for Intra-Articular Injection of ZILRETTA Versus Triamcinolone Acetonide, Immediate Release (TCA-IR) in Subjects With Osteoarthritis of the Hip.” The goal is to test how well a hip injection procedure works when using two different needle sizes with either ZILRETTA, an extended-release steroid, or standard triamcinolone. The focus is practical: improving the reliability of hip injections for patients with hip osteoarthritis, a large and growing pain market.

Intervention/Treatment: The study compares ZILRETTA, a long-acting steroid suspension, with immediate-release triamcinolone acetonide (TCA-IR). Both are given as single injections into the hip joint. ZILRETTA is designed to offer longer pain relief from one injection, while TCA-IR reflects current standard steroid practice. Each drug is tested with either a 20-gauge or 22-gauge spinal needle to see which combination offers a more dependable and practical procedure.

Study Design: This is an interventional Phase 2 study with randomized assignment. Patients are split into four groups in parallel: ZILRETTA with a 20G needle, ZILRETTA with a 22G needle, TCA-IR with a 20G needle, and TCA-IR with a 22G needle. Allocation is 1:1 across the drugs and needle sizes. The study is open-label, meaning both doctors and patients know which treatment they receive. The main purpose is treatment-focused, looking at the success of the injection approach rather than blinded drug comparison.

Study Timeline: The trial was first submitted on May 7, 2025, marking the start of formal regulatory and site setup activity. The most recent update was filed on December 19, 2025, signaling a notable status change and fresh operational information for investors. The trial is currently listed as terminated, which means it stopped earlier than planned and will not move to full enrollment or long-term follow-up as originally intended.

Market Implications: For Pacira (PCRX), the early termination of this hip osteoarthritis procedure study is a modest negative data point rather than a clear readout on ZILRETTA’s efficacy. It may limit near-term expansion of ZILRETTA into the hip indication and raises questions about either feasibility, safety, or strategic priorities in this setting. Investors should view this as slightly dampening sentiment around the breadth of ZILRETTA’s pipeline, though its core knee osteoarthritis use remains the main value driver. Competitors in injectable pain management and standard steroid injections keep a strong foothold in hip osteoarthritis, and this update may slow Pacira’s push to differentiate in that segment. The stock impact will depend on management’s explanation and whether resources are reallocated to more promising trials or indications, but near-term expectations for hip-related upside should be tempered.

The study record has been updated and is listed as terminated, with further details available on the ClinicalTrials.gov portal.

To learn more about PCRX’s potential, visit the Pacira drug pipeline page.