FDA approves single-injection viscosupplement to treat knee osteoarthritis

The FDA has granted marketing approval to Genzyme Corp. for its Synvisc-One product indicated for the relief of knee pain from osteoarthritis. This makes it the first viscosupplementation product available in the United States for single-injection use.

Members of the FDA Orthopaedic and Rehabilitation Devices Panel reviewed Genzyme’s application to market the product in December and voted unanimously to recommend the FDA approve the intra-articular injection therapy.

The single-injection Synvisc-One product has the same indications and contains the same materials as the company’s three-injection Synvisc product approved in 1997. Patients treated with a Synvisc-One injection will ultimately receive the same 6-ml volume of the active ingredient — hylan G-F 20 — as do patients who receive Synvisc, according to a press release.

“The single-injection regimen will provide greater physician and patient convenience,” Jack M. Bert, MD, said in the press release.

Advantages noted

Synvisc-One offers cost advantages since patients need only one office visit for the treatment, said Bert, who is an Orthopedics Today section editor. “Patients suffering from osteoarthritis may experience clinically significant pain relief for up to 6 months, and for some patients, this pain relief could potentially translate into a delay in the need for a total knee replacement.”

At the FDA panel meeting, Andrew I. Spitzer, MD, of Los Angeles, noted an important potential economic advantage relative to the possible approval of Synvisc-One. “A single-injection viscosupplement would virtually eliminate the backlog of patients waiting to see me in the office,” he said.

European data reviewed

In its application to the FDA, Genzyme submitted data from a 21-site pivotal, prospective, randomized, double-blinded controlled trial conducted in Europe involving 253 patients. Patients were randomized to receive a single 6-ml injection of hylan G-F 20 or placebo, with changes on the WOMAC A subscale after 26 weeks as the primary endpoint.

Researchers saw statistically significant differences between the groups’ pain scores in favor of the treatment group. They noted only minor adverse events in the injected knee in both groups.

Genzyme anticipates marketing the product immediately, company officials said in the press release.

Bert has no financial disclosures related to products or companies mentioned. Spitzer has received research/institutional support from and is a paid consultant to Genzyme Biosurgery, but was not compensated in any manner for his comments at the advisory panel meeting.