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Clinical Efficacy


In a large 25-center study, Gel-One Hyaluronate demonstrated superior pain relief from baseline at 13 weeks as compared to a PBS control. Patients receiving Gel-One Hyaluronate experienced, on average, a nearly 40% reduction in pain from baseline (28 mm reduction in WOMAC pain on a 100 mm VAS scale).

Gel-One Hyaluronate is an injectable hyaluronate gel approved for the treatment of osteoarthritis of the knee that does not respond to other conservative treatments. It is the first low-volume viscosupplement injectable available in a single-injection formula.

The highly purified, high viscosity Gel-One Hyaluronate formula requires less volume for effective pain relief with no reports of pseudosepsis (severe acute inflammatory responses) in the clinical trial.

In a major study of 379 randomized patients1 (248 receiving Gel-One Hyaluronate), the findings are clear:

  • Gel-One Hyaluronate demonstrated superior pain relief from baseline at 13 weeks when compared with a PBS control
  • Patients receiving Gel-One Hyaluronate experienced, on average, a nearly 40% reduction in pain from baseline (28 mm reduction in WOMAC pain on a 100 mm VAS scale).
  • Zero incidents of pseudosepsis or any other severe adverse events were reported with Gel-OneHyaluronate treatment.
  • Side effects were as expected, and most commonly included joint swelling, joint effusion and joint pain.

1Of the 379 enrolled patients, 377 patients received either Gel-One Hyaluronate or PBS injection, and 375 patients were analyzed for the Intent to Treat (ITT) population. Patients reported pain with symptomatic OA of the knee defined by WOMAC VAS Pain subscore of ≥40 mm in the study knee and ≤20 mm in the contralateral knee. Patients meeting the following criteria were excluded at randomization: Kellgren-Lawrence Grade 4, severe inflammation or joint effusion in either knee. The ITT population included all treated patients who had any post-injection evaluations.  Table 1 summarizes baseline and patient demographic characteristics for the ITT population.

Table 1: Patient Baseline Characteristics – ITT Population

Variable Gel-One®(N=247) PBS (N=128)
Age (years) Mean (SD) 60.9 (10.2) 60.3 (10.0)
Gender (n) Male 100 (40.5%) 51 (39.8%)
  Female 147 (59.5%) 77 (60.2%)
K-L Score – Study Knee (n) 1 21 (8.5%) 18 (14.1%)
  2 94 (38.1%) 47 (36.7%)
  3 132 (53.4%) 63 (49.2%)
Study Knee      
WOMAC Pain Subscore (mm) Mean (SD) 70.7 (14.4) 68.0 (13.1)
Total WOMAC Score (mm) Mean (SD) 69.5 (16.0) 67.8 (14.7)
WOMAC Physical Function (mm) Mean (SD) 68.9 (17.4) 67.6 (15.8)
WOMAC Stiffness (mm) Mean (SD) 71.6 (17.5) 69.3 (17.3)
Contralateral Knee      
WOMAC Pain Subscore (mm) Mean (SD) 7.3 (5.5) 7.6 (5.6)

Summary of Secondary Effectivenessa Endpoints at Week 13 – ITT Population

Effectiveness Measuresb Model-Estimated Advantage (Gel-One® – PBS) Two-sided Lower 95% Confidence Limit (mm) Two-sided P-valuec
Total WOMAC Score 5.64 mm -0.20 0.0583
WOMAC Stiffness 4.91 mm -1.31 0.1216
WOMAC Physical Function 5.42 mm -0.47 0.0714

a Based on the quadratic spline model at week 13.
b WOMAC Scale is 100mm.
c P-value was not adjusted for multiplicity of secondary endpoints.

There were no serious AEs or pseudoseptic reactions related to Gel-One® Hyaluronate injection.

Conclusions: The study results demonstrated that a single injection of Gel-One Hyaluronate is safe and effective for treatment of pain in osteoarthritis of the knee in patients who have failed to respond to nonpharmacologic therapy, NSAIDs or simple analgesics.

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