BTG plc: Preliminary Results Of VARISOLVE European Phase III Trial.

Business Editors/Health/Medical Writers

LONDON--(BUSINESS WIRE)--Aug. 29, 2003

Trial objectives met - VARISOLVE(R) shown similar in efficacy to,

and with significant potential advantages over, existing treatments

BTG plc (LSE: BGC), the global technology commercialization company, today announced the preliminary results of a pivotal European Phase III trial of the VARISOLVE(R) endovenous microfoam procedure, being developed by its subsidiary Provensis Ltd. as a new treatment for varicose veins.

The overall response rate in patients treated with VARISOLVE(R) was 83.4%, in line with expectations. This response rate is based on a very stringent primary endpoint, being the achievement of both occlusion (closure) of the treated vein and elimination of significant reflux (flow of blood back into the vein) as measured three months after treatment. Using the more conventional success criterion of either occlusion or elimination of reflux, VARISOLVE(R) achieved a response rate of 89.6%.

The trial was designed to establish whether VARISOLVE(R) is similar in efficacy to conventional treatments (sclerotherapy or surgery) in the treatment of moderate to severe varicose veins, based on the primary endpoint. In total, 654 patients (68% female) were treated at 15 centers in the UK, France, The Netherlands, Belgium, Germany, Sweden and Italy. Patients were initially assigned by their physician for treatment with either sclerotherapy (liquid or foam) or surgery. Within each of these two cohorts they were then randomized in a 1:2 ratio to receive the assigned treatment or VARISOLVE(R). There was no significant difference between the overall response rate of patients treated with VARISOLVE(R) (83.4%) and established alternative treatments (87.7%), hence the main goal of the trial was established. The trial also suggested significant potential benefits over existing treatments:

-- In the surgery cohort, VARISOLVE(R) patients required on

average only 2 days to return to normal activities following

treatment compared with 13 days for patients treated

surgically.

-- Patients treated with VARISOLVE(R) experienced less pain than

surgery-treated patients, measured using an established

"visual analogue score" method after 1, 3 and 7 days.

-- Only 7.8% of legs required re-treatment with VARISOLVE(R),

whereas 24.8% of conventional sclerotherapy injections had to

be repeated.

Dr J-P Gobin, Independent Phlebologist in Lyon and lead investigator in France for the Phase III trial, commented: "This trial has shown that VARISOLVE(R) microfoam has great potential for the treatment of varicose veins. The microfoam is sterile, uniform and stable, and induces rapid onset of venospasm. It is convenient to administer, for both patient and physician, and treatment can be completed in a single session."

In total, 435 patients received VARISOLVE(R), 125 received conventional sclerotherapy and 94 were treated with surgery. For the primary endpoint (both elimination of significant reflux and occlusion of the treated vein), VARISOLVE(R) was similar in efficacy to the alternative treatments overall: 363 of 435 (83.4%) VARISOLVE(R) patients responded, while 192 of 219 (87.7%) patients receiving established treatments responded. Within the sclerotherapy cohort, 93.8% of VARISOLVE(R) patients responded and 88.8% of sclerotherapy patients responded. In the surgery cohort, 68.2% of VARISOLVE(R) patients responded compared with 86.2% of surgery patients.

Further analysis using either elimination of reflux or occlusion of the treated vein as the criterion for a positive response showed that VARISOLVE(R) had an overall response rate of 89.6%. In the sclerotherapy cohort the response rates with VARISOLVE(R) were 96.3% for treatment of the long saphenous vein (LSV)(1.) and 95.3% for treatment of the short saphenous vein (SSV), compared with 96.9% and 92.9% respectively with sclerotherapy. In the surgery cohort, the response rates with VARISOLVE(R) were 84.6% for the LSV and 66.7% for the SSV, compared with 87.5% and 58.3% respectively with surgery.

Ian Harvey, Chief Executive Officer of BTG, commented: "We are very pleased with these results, which confirm our view that VARISOLVE(R) represents a significant advance in the treatment of varicose veins with similar efficacy to, but major advantages over, existing treatments. We look forward to filing the first European marketing authorization application in 2004, as planned."

These preliminary results will be presented to an international audience of phlebologists at the UIP congress in San Diego, USA, on August 30. The final study report is due later this year.

About BTG

BTG finds, develops and commercializes emerging technologies in the life and physical sciences. These innovations are protected by a strong portfolio of intellectual property that BTG develops and enhances. BTG then captures the value in these technologies through licensing and venturing activities. From the origins of its business in 1949, BTG has commercialized major innovations such as Magnetic Resonance Imaging (MRI), recombinant factor IX blood-clotting protein, Campath(R) (alemtuzumab) and Multilevel Cell (MLC) memory. BTG is quoted on the London Stock Exchange under the symbol "BGC" and operates from offices in London and Philadelphia, with representation in Tokyo. BTG operates through wholly owned subsidiaries, BTG International Ltd. and BTG International Inc. in the UK and USA, respectively. Further information on BTG can be found at www.btgplc.com.

Provensis Ltd. is a wholly owned subsidiary of BTG that was established in 1999 to develop and commercialize the VARISOLVE(R) procedure, to which the company has an exclusive worldwide licence. Based in Middlesex, UK, Provensis is engaged in the development, quality assurance, clinical trials, regulatory affairs, manufacturing and commercialization of VARISOLVE(R).

(1.) The short saphenous vein runs up the back of the leg from the foot to the knee. The long saphenous vein runs from the foot up the inner side of the leg through the thigh to the groin.