BTG, a specialist healthcare company, has presented positive late-stage phase III data on its varicose vein therapy Varisolve™ (polidocanol endovenous microfilm - PEM). PEM is a unique patent-protected drug/device combination that produces highly uniform CO2/O2 polidocanol endovenous microfoam engineered to improve safety and efficacy in the treatment of varicose veins. It is injected directly into the incompetent vein under ultrasound guidance, where it first displaces blood and then the polidocanol chemically ablates the inner lining of the vein wall, causing the vein to close.

VANISH-2 randomised 235 patients who to one of three dose concentrations (0.125%, 0.5% or 1.0%) of PEM (n = 176) or “vehicle”, effectively a placebo comparator (n = 59). The primary endpoint was an improvement in symptoms recorded by patients using a patient-reported outcomes instrument, VVSymQ™. The VVSymQ™ score is a patient-reported outcome measure of varicose vein symptoms developed and validated by BTG in accordance with FDA guidelines. Patients scored a variety of symptoms such as swelling and aching using a daily electronic diary for 10 days prior to treatment (baseline) and for an additional 10 days prior to the primary endpoint at eight weeks following treatment.

Patients treated with PEM (0.5% or 1.0% dose concentrations) demonstrated a statistically significant improvement in the primary endpoint, compared with patients who received placebo (p < 0.0001). The study also met secondary and tertiary endpoints (no absolute data were reported in the company press release).

Chemically induced thrombosis was reported in 5.8% of PEM treatments (n=984), of which 0.5% were symptomatic deep vein thrombosis of the upper leg and 0.7% of the lower leg, respectively. There were no cerebrovascular events or pulmonary emboli reported in any study.

Further data are anticipated in 2012 for VANISH-1, and another study in which Varisolve is used following heat ablation.