Trial summary1

  • ZILRETTA® (triamcinolone acetonide extended-release injectable suspension) was studied in a multicenter, international, randomized, double-blind, parallel-arm, placebo- (saline) and active-controlled (TAcs) trial that evaluated patients with moderate to severe OA pain of the knee (N=484)
    • Patients received a single intra-articular injection of ZILRETTA (32 mg, n=161), saline (n=162), or TAcs (40 mg, n=161) and were followed for up to 24 weeks, with daily pain reported and evaluations at baseline and at Weeks 4, 8, 12, 16, 20, and 24
Key outcomes

Pivotal trial outcome measures:

Average daily pain (ADP): Measures daily pain intensity on a 0 to 10 numeric rating scale (NRS)

ADP=average daily pain; OA=osteoarthritis; TAcs=triamcinolone acetonide crystalline suspension.

Phase 3 study

Rapid, persistent, and proven relief from OA knee pain

Patients experienced a significant reduction in OA knee pain vs saline control after a single injection1

Pain relief in patients with moderate to severe knee OA

  • Rapid—4 days median time to onset with ZILRETTA® (triamcinolone acetonide extended-release injectable suspension) and 3 days with TAcs1*
  • Substantial—50% reduction from baseline at Week 123
  • Persistent—reduction in ADP each week from Weeks 1 to 12, extending to Week 161,4

ADP=average daily pain; BL=baseline; LS=least squares; NRS=numeric rating scale; OA=osteoarthritis; SE=standard error; TAcs=triamcinolone acetonide crystalline suspension.


The majority experienced no/mild knee pain as early as Week 1 and sustained through Week 123

  • Percentage of 161 ZILRETTA-treated patients experiencing no/mild knee pain at
    Week 4 (21%/49%), Week 8 (22%/47%), and Week 12 (20%/49%), respectively4
~60% of patients experienced no/mild knee pain at Week 163

NRS=numeric rating scale; OA=osteoarthritis.

ZILRETTA demonstrated significant improvement in ADP and WOMAC A pain scores in patients with unilateral OA vs TAcs1

  • ZILRETTA demonstrated significant (P<0.05) improvement in ADP intensity compared with saline control from Weeks 1 to 24 and with TAcs from Weeks 4 to 21

Safety was similar among treatment groups, with most being mild or moderate.
  • ZILRETTA demonstrated significant (P<0.05) improvements in WOMAC A scores compared with saline control on Weeks 4, 8, 12, and 24 and compared with TAcs on Weeks 4, 8, 12,
    and 24

Results from a post hoc analysis of a ZILRETTA Phase 3 trial

ADP=average daily pain; LSM=least squares mean; OA=osteoarthritis; SE=standard error; TAcs=triamcinolone acetonide crystalline suspension; WOMAC=Western Ontario and McMaster Universities Osteoarthritis Index.


ZILRETTA significantly improved outcomes among patients who reported consistent moderate to severe OA pain in both ADP and WOMAC A scales3

  • Change from baseline in ADP score was significantly (P<0.05) improved with ZILRETTA compared with TAcs each week from Weeks 5 to 19 and compared with saline control each week from Weeks 1 to 20

  • ZILRETTA demonstrated statistically significant (P<0.05) improvements in WOMAC A scores compared with TAcs at Weeks 4, 8, and 12 and compared with saline control at Weeks 4, 8, 12, and 16
  • ZILRETTA reduced WOMAC A pain scores from baseline by as much as 59% (Week 4); the largest reduction in pain resulting from TAcs treatment was 46% (Week 4)

Results from a post hoc analysis of a ZILRETTA Phase 3 trial

*Moderate to severe pain defined as ADP scores ≥5 to ≤9 (per original inclusion criteria) and WOMAC A
scores ≥2.

ADP=average daily pain; TAcs=triamcinolone acetonide crystalline suspension; WOMAC=Western Ontario and McMaster Universities Osteoarthritis Index.


Among these consistent pain reporters, 28% of ZILRETTA patients reported no pain at Week 12, compared with 8% of TAcs patients3

Results persisted through Week 16 with ~20% of patients treated with ZILRETTA experiencing no pain compared to ~9% for TAcs.

Results from a post hoc analysis of a ZILRETTA Phase 3 trial

ADP-intensity scores rated on a 0-10 NRS, with 0 indicating “no pain” and 10 indicating “pain as bad as you can imagine.”

ADP=average daily pain; NRS=numeric rating scale; TAcs=triamcinolone acetonide crystalline suspension.