From the Guidelines
Zilretta is a suitable treatment option for patients with osteoarthritis knee pain, providing extended pain relief with a single 32 mg intra-articular injection, as supported by recent studies 1. The standard dose of Zilretta is a single 32 mg injection into the affected knee joint, with effects typically lasting about 12 weeks, significantly longer than traditional steroid injections.
- Patients should be aware that this is not a permanent solution but provides extended pain relief compared to standard corticosteroid injections.
- The extended-release microsphere technology allows for gradual medication release, reducing systemic absorption and potentially minimizing side effects like blood glucose elevation in diabetic patients.
- While Zilretta can be repeated, it's generally not recommended more than 2-3 times per year in the same joint.
- Common side effects include joint pain, headache, and joint swelling. This treatment is particularly beneficial for patients who need longer-lasting relief than conventional steroid injections provide but aren't ready for surgical intervention, as it can improve their quality of life and reduce morbidity associated with osteoarthritis knee pain 1. In the context of psoriasis and psoriatic arthritis management, biologic medications like etanercept and infliximab have shown efficacy in treating various forms of psoriasis, including scalp and nail psoriasis, and can be combined with other agents to increase efficacy 1. However, the use of Zilretta is not directly related to the treatment of psoriasis or psoriatic arthritis, and its primary indication is for osteoarthritis knee pain. Therefore, the recommendation for Zilretta use should be based on its efficacy and safety profile for osteoarthritis treatment, rather than its potential use in psoriasis or psoriatic arthritis management.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Zilretta Overview
- Zilretta is a triamcinolone acetonide extended-release injection approved for the management of osteoarthritis pain of the knee 2
- It is administered as a single, 5 mL intra-articular injection and is formulated in poly (lactic-co-glycolic acid) (PLGA) microspheres that slowly release triamcinolone acetonide in the synovium 2
Efficacy and Safety
- Triamcinolone acetonide extended-release has been shown to significantly improve mean average daily pain intensity in patients with knee OA relative to placebo 2
- It has also been shown to improve pain, stiffness, and physical function according to WOMAC criteria relative to placebo and triamcinolone acetonide crystalline suspension (CS) 2
- The treatment is generally well tolerated, with a tolerability profile similar to that of triamcinolone acetonide CS and placebo 2
- A study found that 10 mg of triamcinolone acetonide is non-inferior to 40 mg in improving pain in patients with symptomatic knee OA 3
Comparison with Other Treatments
- Triamcinolone acetonide extended-release has been compared to other treatments, including cryoneurolysis, intra-articular hyaluronic acid injections, and nonsteroidal anti-inflammatory drug injections 4
- The study found that triamcinolone acetonide extended-release was associated with the lowest pain, greatest pain reduction, and highest prevalence of patients achieving minimally clinically important difference (MCID) relative to other treatments 4
Mechanism of Action
- Triamcinolone acetonide works by reducing synovitis and alleviating pain in the osteoarthritic joint 5
- The use of biomaterial-based local triamcinolone acetonide release may prolong the suppression of pain without the need for multiple injections 5
Clinical Outcomes
- A randomized double-blind placebo-controlled trial found that intra-articular triamcinolone injection was effective in symptom control and improving functional outcome in clinically diagnosed osteoarthritis of knees in a community setup 6
- The study found significant pain relief in the group receiving triamcinolone at two and six weeks, but not at twelve weeks 6