Ranbaxy pushes Pravosin to phase-1 trials

Ranbaxy Laboratories has received the nod from the Drug Controller General of India for conducting phase-1 clinical trials of the much-awaited molecule RBx 2258 used in the treatment of benign prostatic hyperplasia. The company will commence trials in early June 1999.

The molecule has been named 'Pravosin' after Parvinder Singh, chairman and managing director of the company, and is the first new chemical entity originating from Ranbaxy. The company is understood to have also developed a lead molecule in the respiratory segment, for which an investigational new drug (IND) application is likely to be filed in 2000.

Benign prostatic hyperplasis, or enlargement of the prostate gland, is an ailment of ageing males. It is characterised by obstruction of the urethra by the enlarged gland resulting in frequent micturation (urination) and poor urine stream. The worldwide market for antidotes for this condition is estimated around $3 billion by the year 2003.

To offset any failures associated with RBx 2258 during phase-1 trials, Ranbaxy Laboratories has started work on another lead molecule in the same area.

Before a molecule enters the market, it has to undergo three stages of clinical trials on human subjects. The phase-1 trial is conducted on normal humans using multiple dosage levels to evaluate safety and tolerability (toxicity). This is followed by phase 2(a) to ascertain safety and efficacy and phase 2 for efficacy and effectiveness of dosage at the final level. Phase 3 is the final and confirmatory trial conducted on a large human population.

Though Ranbaxy is utilising internal resources for phase-1 trail of Pravosin, it may consider licensing the product to multinational companies for further development. "We cannot go world-wide on our own," says D S Brar, president, Ranbaxy Laboratories, hinting that a licensing deal is imminent.

The company is encouraged by the pre-clinical response to Pravosin, and claims that the lead molecule is orally active and several-fold more uro-selective than other benign prostatic hyperplasia products.