LAS VEGAS – A novel lipid formulation of ibuprofen given at 1,200 mg/day proved noninferior to high-dose standard ibuprofen at 2,400 mg/day for management of episodic knee pain flares in a phase III randomized trial, and it accomplished this with significantly fewer gastrointestinal side effects, Sita M.A. Bierma-Zeinstra, MD, reported.
Episodic flares of knee pain are a disabling feature of knee osteoarthritis that can occur at all stages of the disease, including prior to clinical diagnosis. There is a need for a fast-acting analgesic designed for short-term use with minimal side effects to provide pain relief during these flares. This was the motivation for developing Flarin, a lipid formulation soft-gel capsule of ibuprofen that is effective at less-than-standard doses of the conventional NSAID, she explained at the World Congress on Osteoarthritis.
She presented results of a triple-arm randomized trial conducted in primary care offices in the United Kingdom and the Netherlands. The phase III study included 462 adults up to age 70 with a history of at least one flare of knee pain during the prior year, along with another such episode underway for less than 24 hours at the time of enrollment. The patients were assigned to the novel lipid formulation of ibuprofen in soft-gel capsules at 1,200 mg/day or to conventional ibuprofen in soft-gel capsules at either 1,200 or 2,400 mg/day.The primary outcome was change in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale after 5 days of treatment. The score dropped from a mean of 5.72 at baseline out of a possible maximum of 10 to 3.05 in the lipid ibuprofen group, from 5.6 to 3.26 in patients on standard ibuprofen at 1,200 mg/day, and from 5.61 to 2.82 in subjects on standard ibuprofen at 2,400 mg/day. Those between-group differences were not statistically significant, reported Dr. Bierma-Zeinstra, professor of osteoarthritis and related disorders at Erasmus University Medical Center in Rotterdam.
In contrast, the rate of gastrointestinal side effects was significantly different across the three treatment arms: 16.2% in the lipid ibuprofen group, 22.6% with conventional ibuprofen at 1,200 mg/day, and 28.3% with ibuprofen at 2,400 mg/day, she said at the congress, which was sponsored by the Osteoarthritis Research Society International.
The group on the investigational formulation of ibuprofen also showed a consistent trend for superior results on the WOMAC swelling, pain, stiffness, and function subscales after 5 days of treatment, although only the improvement in swelling achieved statistical significance, Dr. Bierma-Zeinstra continued.
Flarin is approved and marketed in the United Kingdom. Infirst Healthcare, the novel NSAID’s developer and the sponsor of the phase III randomized trial, is seeking to gain regulatory approval throughout Europe. The U.K. company also has an agreement with McNeil Consumer Pharmaceuticals to market its products in the United States, once approved.
Dr. Bierma-Zeinstra reported having received a research grant from Infirst.