US group Anika Therapeutics has been hit by the failure of its viscosupplement Cingal to hit targets in a Phase III trial comparing its effectiveness to a standard treatment in patients with osteoarthritis of the knee.

Shares in the group dropped more than 20 percent after it announced that Cingal, a combination of cross-linked HA and triamcinolone hexacetonide (TH), failed to reduce pain significantly more than TH alone at 26 weeks.

The firm did stress that a previous trial has already confirmed the safety and efficacy of Cingal in this setting, and that while Cingal achieved greater pain reduction than its comparator at every time point in the study, the difference at 26-weeks did not reach statistical significance.

“While it has been observed that TH has a longer duration of effect than other corticosteroids, the results in this study were surprising,” said Prof. Laszlo Hangody, the global principal investigator of several Cingal trials.

“Nevertheless, the patient response to Cingal in this study was strong as patients received statistically and clinically meaningful rapid and long-lasting improvement in symptoms compared with base-line, consistent with the previous study as well as my experience in my practice.

“Taken together, the results of the two Phase III studies validate the effectiveness of this novel combination for use in patients with knee osteoarthritis,” he stressed.

Joseph Darlin, Anika’s president and chief executive, also expressed surprise that the trial endpoint was missed, but noted that the firm will continue to monitor the results of the ongoing three-month extension study.

“We are actively reviewing the data and our plan is to work closely with regulators to come to an understanding of the next steps required to gain U. regulatory approval of Cingal,” he said.