NeoPharm, Inc. has announced that patient enrolment has commenced in a multi-centre phase II clinical trial of LE-SN38 in the treatment of patients with metastatic colorectal cancer. The trial is being conducted by Cancer and Group B (CALGB), an oncology clinical research group sponsored by the National Cancer Institute (NCI).

LE-SN38 is NeoPharm's NeoLipid liposomal formulation of SN-38, the active metabolite of irinotecan (Camptosar), a chemotherapeutic pro-drug approved for the treatment of advanced colorectal cancer.

"The CALGB is pleased to be collaborating with NeoPharm on the clinical development of LE-SN38," said Richard L. Schilsky, MD, Professor of Medicine and Associate Dean for Clinical Research, Biological Sciences Division of the University of Chicago, and Chairman of the Cancer and Leukemia Group B. "We welcome the opportunity to provide colorectal cancer patients with an additional clinical trial treatment option."

"Our LE-SN38 drug candidate, as well as the underlying NeoLipid drug delivery platform are an important part of our oncology portfolio," said Guillermo Herrera, NeoPharm's president and CEO. "We are pleased to be moving LE-SN38 into phase II testing with CALGB, one of the premiere oncology clinical research groups, in the hope of eventually providing colorectal cancer patients with a new and potentially less toxic treatment option."

The phase II trial will seek to enrol up to 54 patients. The primary endpoint of the trial is overall tumour response rate (ORR) following treatment with LE-SN38 as a second-line treatment in patients with metastatic colorectal cancer. Other endpoints include determining the safety profile of LE-SN38 in this patient population, as well as the progression-free survival (PFS) and overall survival (OS) for the patients treated.

Patients will receive LE-SN38 by intravenous infusion over 90 minutes every 21 days as long as the tumour does not grow or patients are unable to tolerate the treatment.

It is currently expected to take up to 1 year to fully enrol the trial. An initial assessment of tumour response will be made after the first 21 patients are treated. Enrolment will continue while tumour response is being evaluated in the initial group of patients. If results from the CALGB study appear promising, future LE-SN38 development could include possible development and initiation of a phase III trial.

Colorectal cancer develops in the colon (large intestine) and/or the rectum, and affects more than 150,000 patients annually. According to the National Cancer Institute (www.cancer.gov), colorectal cancer is the third most common cancer and the third leading cause of cancer-related mortality in the United States. Colorectal cancer is associated with severe morbidities, including bowel obstruction, liver failure, pain, weakness, and wasting. Until age 50, men and women have similar incidence and mortality rates; after age 50, men are more vulnerable. The NCI estimates that approximately $8.4 billion (in 2004 dollars) is spent annually in the United States on treatment of colorectal cancer.

LE-SN38 is the Company's NeoLipid Liposomal formulation of SN-38, the active, but poorly soluble, metabolite of Camptosar, a chemotherapeutic pro-drug, which is used as a first-line and second-line treatment for advanced colorectal cancer. A pro-drug is a compound that is converted into the active drug in the body. However, Camptosar is converted into SN-38 in colorectal cancer cells at different rates in different patients, and this variability in conversion rates may result in suboptimal treatment. By employing the Company's proprietary NeoLipid technology to directly deliver SN-38, the Company hopes to minimize treatment variability.

A phase I clinical trial was completed in 2005 and showed the potential for decreased side effects, particularly diarrhoea, compared to published results of Camptosar. The results of that trial were presented at the American Society of Clinical Oncology (ASCO) meeting in June 2005, and were used to determine the phase II study dose.