With Bayer AG presenting an encouraging picture of the human trials of the 500 mg Cipro OD, outlicensed by Ranbaxy Laboratories Limited to Bayer AG, the Indian company is drawing closer to another milestone and royalty payment from the German drug major.

Cipro OD (renamed Cipro XR by Bayer) is indicated for the treatment of uncomplicated urinary tract infections.

An industry source said here today that the product may be launched in the US market by the end of the first quarter of calendar year 2003. With the generics litigation behind its back, the deck is clear for the company to go ahead with the launch of the once-daily formulation, an novel drug delivery system developed by RLL scientists.

The NDDS springs from Ranbaxy''s patented gastro-retentive drug-delivery technology that will help extend the life cycle of ciprofloxacin worldwide.

The company, it may be recalled, had launched the product in the Indian market last year itself under the brand name Cifran OD. Till the launch, ciprofloxacin was required to be taken twice a day, making patient compliance difficult. Sales of Cifran have not looked back since.

Results announced yesterday show that 500 mg Cipro XR given once-a-day over three days for uncomplicated urinary tract infection (UTI) was comparable in safety and efficacy to the conventional twice-daily dose (250 mg) of Cipro.

The results of this US multi-center clinical trial were presented at the 42nd Interscience Conference on Antimicrobial Agents and Chemotherapy in San Diego (ICAAC) by Dr. Ernie Riffer of Central Phoenix Medical Clinic, AZ.

Dr Riffer said, "This study showed that the new extended release formulation of once-daily ciprofloxacin was comparable to twice-daily ciprofloxacin over a three-day course of therapy for uncomplicated UTIs."

Uncomplicated UTIs are responsible for an estimated 8 million physician visits per year in the US. "We developed Cipro XR in direct response to the needs of our customers. We asked physicians what was most important to their UTI patients and once-a-day dosing was a common response," said Dr. Larry Posner, senior vice president, Pharmaceutical Development; worldwide head, Regulatory Affairs, Ethical Pharmaceuticals, Bayer Corporation.

The prospective, randomized, double-blinded study followed the treatment of 891 adult women with clinical signs and symptoms of acute uncomplicated UTI, including pyuria, and a positive pre-therapy urine culture. The treatment groups were similar with respect to demographics and infection characteristics.

The new once-daily formulation was developed using a bilayer matrix of the active ingredient ciprofloxacin. This new formulation enables the rapid release of ciprofloxacin, which distributes to the serum and tissues within hours.

This is followed by a second extended release of the active ingredient over 24 hours. The prospective, randomized, blinded study followed the treatment of 891 women with clinical symptoms of acute uncomplicated UTI.

At the first assessment point, 4-11 days post-treatment, bacteriologic eradication was achieved in 94 per cent in the once-daily therapy arm and 94 per cent in the twice a day-treated patients; clinical cure was observed in 95 per cent of the once-daily treated patients compared to 93 per cent of twice-daily therapy patients.

Eradication of E. coli, the most predominant organism, was 97 per cent for each group. Bayer submitted this New Drug Application (NDA) to the US FDA in March 2002 to market Cipro XR for the treatment of uncomplicated UTI in the once daily tablet formulation used in this trial.