BresaGen halts study on leukaemia drug

A leukaemia drug developed by Adelaide biotech BresaGen (ASX: BGN) will go back to the drawing board after it was found not to be as effective as previously thought against one form of the disease.

The company's United Kingdom licensing partner British Biotech has announced it will suspend Phase II trials of E21R in the treatment of patients with AML.

The study, which began a year ago, was halted after an independent pre-clinical study failed to support the high incidence of apoptosis, or cell death, found in previous work.

Trials of the drug in other forms of the disease - including myelomonocytic leukaemias, chronic myelomonocytic leukeamia (CMML), and juvenile myelomonocytic leukaemia (JMML) - will continue as planned.

BresaGen vice-president and chief operating officer Dr Meera Verma said British Biotech had decided to slow down the AML trial because it wished to do more pre-clinical work on the technology and redesign the research protocols.

"The incidence of cell killing doesn't look in AML as much as it did earlier in the piece," Verma said.

"It's obviously always annoying when things get delayed, because we were hoping to get in some efficacy results early next year and now that's likely to be delayed three to four months."

Verma said Phase I tests of E21R were conducted on patients with solid tumour cancers in 2000.

Specific leukaemia tests were done in pre-clinical laboratory studies before world-wide rights to the drug were licensed out to British Biotech.

Under the agreement, British Biotech is responsible for conducting the clinical studies necessary to obtain regulatory approval for E21R as a treatment for AML.

The agreement also gives the company exclusive rights to commercialise the drug for all leukaemic and non-leukaemic indications.

In August 2001, British Biotech started a Phase II study to investigate GM-CSF antagonist E21R's efficacy, safety, tolerability and pharmacokinetics in AML patients.

In a market statement, BresaGen said it was continuing to recruit patients to a pilot Phase II study in CMML.

Also, in March 2002, the European Commission designated E21R as having orphan drug status for the treatment of JMML, a rare and deadly disease affecting very young children.

The drug is also being used in a pilot Phase II rheumatoid arthritis study in which patients will receive four 10-day courses of daily subcutaneous injections of E21R.

At the time of writing, shares in BresaGen were unchanged at 65 cents.