Positive new health economics analysis of Zilretta for the treatment of knee osteoarthritis (OA) pain.- Flexion Therapeutics, Inc.

Flexion Therapeutics, Inc. announced the findings from a new health economics analysis of Zilretta (also known as FX006), the company's lead investigational candidate for the treatment of knee osteoarthritis (OA) pain. The study, which utilized established health economic metrics, demonstrated that Zilretta has the potential to be a cost effective therapy in this indication. The findings were presented at the International Society for Pharmacoeconomics and Outcomes Research (ISPOR) 22nd International Meeting, taking place May 20-24 in Boston.

The study was designed to estimate the impact of Zilretta on overall quality of life in patients with knee OA and to evaluate its cost-effectiveness compared with other therapeutic interventions including conventional care (over-the-counter non-steroidal anti-inflammatory drugs (NSAIDs), acetaminophen, physical therapy and assistive devices), diclofenac (a prescription NSAID) and hyaluronic acid (HA) injections. With respect to Zilretta, the study utilized previously collected WOMAC5 scores from 324 patients enrolled in three separate Phase II and Phase III randomized clinical trials of Zilretta in patients with knee OA pain.

Using an established algorithm, the authors were able to convert the WOMAC assessments to Health Utilities Index Mark 3 (HUI-3) scores. The cost-effectiveness analyses were based on a Quality Adjusted Life Year (QALY) gain, which was calculated from the improvement in HUI-3 scores over six months. For the analysis, Zilretta was assigned a hypothetical cost of $500 per treatment and the comparator treatments were assigned their respective 2016 wholesale acquisition costs. Key study findings include: Zilretta produced an average QALY gain from baseline of 0.189 per six months, which suggests a greater improvement in quality of life compared with the average values for conventional care (0.030), diclofenac (0.078) and HA injections (0.109). Zilretta yielded a cost per QALY estimate of $3,201, compared with cost per QALY estimates for conventional care ($10,717), diclofenac ($2,708) and an average HA treatment course ($13,389).The poster (PMS28) is displayed at ISPOR on Monday, May 22 . The abstract and the poster can be found on the ISPOR website.