LONDON - Stanford Rook Ltd. said its immunotherapeutic SRL172 will enter a multicenter Phase III trial in lung cancer, following presentation of data from one of three arms of a randomized Phase II study.
Recruitment of more than 400 patients for the Phase III trial will start in the fourth quarter of 1998.
The results of a study of SRL172 in 28 patients with symptomatic non-small cell lung cancer were presented by Mary O'Brien, a clinical investigator with the Royal Marsden National Health Service Trust, to a joint meeting of the British Oncology Association and the Association of Cancer Physicians earlier this month. These showed that mean survival of patients treated with chemotherapy alone was 7.5 months, while mean survival of patients who received chemotherapy plus SRL172 was 9.7 months.
“The response from at least a year's follow-up confirm those from an earlier analysis, that the response rate is higher in patients who receive SRL172 with standard chemotherapy than in those who receive chemotherapy alone,“ said O'Brien. “The combination treatment prolongs the duration of remission and the length of overall survival.“
Thomas Lang, director of business development at Stanford Rook told BioWorld International, “We are very pleased about the move into Phase III. The Phase II results are not statistically significant because of the small numbers involved. But the trend is marked enough for O'Brien to recommend a move into a large confirmatory study. To get that kind of survival benefit is good.“
The protocol for Phase III has been submitted for approval and a number of centers in Europe have agreed to take part. “Mary O'Brien will now be encouraging other oncologists to take part,“ said Lang.
The company expects results by the end of the year from the two other arms of the Phase II study. The second arm involved 28 patients with asymptomatic non-small-cell lung cancer, the third arm 28 patients with small-cell lung cancer.
At the same time Stanford Rook is to begin a Phase II study in 80 renal cancer patients. “In this study SRL172 will be administered as a single agent as there is no recognized chemotherapy for these patients. This will provide important supplementary information on the effect of SRL172 alone,“ Lang said.
SRL 172 is a suspension of killed Mycobacterium vaccae which stimulates the immune system to fight disease.
While the Phase III in lung cancer will involve patients in the terminal stages of the disease, Lang said, if successful, it will open up the possibility of treating earlier stage patients.
“SRL172 is well tolerated so the option is that patients can be treated with it earlier,“ he added. “Unlike chemotherapy, it is not toxic and does not impact on the quality of life.“ *