LONDON — An adhesion-prevention solution made from 4% icodextrin significantly reduced the incidence of adhesions after gynecologic laparoscopic adhesiolysis, compared with Ringer's lactate solution, according to results of a multicenter, double-blind clinical trial.
The product, called Adept, is made by ML Laboratories PLC of Leicestershire, England. It has been licensed for use in Europe since 1999; in the United States, it is licensed only as an investigational medical device, said Elizabeth Peers, Ph.D., head of research and development for the company.
The study of postsurgical adhesions after gynecological laparoscopic adhesiolysis—known as the PAMELA study—will form the basis of the company's submission for Food and Drug Administration approval, she told this newspaper. The company plans to apply for approval this year.
Data from the PAMELA study were presented at the annual congress of the International Society for Gynecologic Endoscopy. The study randomized 449 laparoscopic adhesiolysis patients to intraoperative irrigation and instillation of Adept or Ringer's lactate solution (RLS) during a first surgical procedure. The fluids were irrigated at 100 mL/30 min intraoperatively, and a postoperative instillate of 1 L was left in the pelvic cavity.
Because of its high molecular weight, Adept is absorbed slowly via the lymphatic system and remains in the pelvic cavity, providing hydroflotation for 3–5 days post surgery, the critical time for adhesion formation, said Dr. Peers.
During the initial surgical procedure, the presence of adhesions, their extent (localized, moderate, or extensive) and severity (mild or severe) were assessed at 23 anatomical sites. A reassessment made on second-look laparoscopy 4–8 weeks later analyzed the change in number of sites with adhesions, as well as the number of new adhesions.
Adept performed significantly better than RLS on both measures, with 53% of Adept-treated patients free of new adhesions, compared with 43% of RLS patients.
Additionally, Adept-treated patients had a greater reduction in the mean number of sites with adhesions—from 10.3 to 7.9—compared with a reduction from 10.3 to 8.3 for RLS-treated patients.
Subgroups of 192 and 199 patients contributed to a separate analysis assessing American Fertility Society (AFS) scores for adnexal adhesions. Mean initial AFS scores were 7.4 for the Adept group and 7.3 for the RLS group. At second look, the score dropped to 4.9 for the Adept group and 6.2 for the RLS group—significantly favoring the Adept treatment.
Additionally, among patients whose primary diagnosis was infertility, the AFS score was reduced in significantly more Adept than RLS patients (51% vs. 30%).
The fact that any improvements were noted in patients treated with RLS was unexpected, since RLS is not known to reduce adhesions. This finding may be associated with the large volumes of both fluids as postsurgical instillates. “One liter is considerably more than is generally left in the pelvic cavity,” she said.