ALFACELL initiates Phase III clinical trial for asbestos-related cancer.

BLOOMFIELD, N.J.--(BUSINESS WIRE)--May 15, 1997--

Phase II Interim Analysis Presented at the 4th International

Mesothelioma Conference

ALFACELL Corp. (NASDAQ: ACEL) presented today an update of its on-going Phase II clinical trial of its flagship product, ONCONASE(R), in patients with advanced malignant mesothelioma.

The interim results, entitled "The use of ONCONASE for Patients with Advanced Malignant Mesothelioma", were presented at the Fourth International Mesothelioma Conference, which is being held at the University of Pennsylvania, Philadelphia, from May 13-15, 1997.

Malignant mesothelioma (MM) is a fatal cancer occurring in the lining of the chest and/or abdomen and is often associated with prior asbestos exposure. MM afflicts approximately 3,500 people in the United States each year and is frequently diagnosed up to 20-40+ years after exposure. Most patients treated with chemotherapy do not respond favorably; patients often die of locally progressive disease within 6-12 months of diagnosis.

Thirty-seven percent of the 63 patients analyzed demonstrated evidence of objective clinical activity and had median survival times (MSTs) of 10.1 months from day 1 of treatment and 24.7 months from date of diagnosis. Of the patients enrolled at least one year prior to this analysis, 42% survived 1 year after being treated with ONCONASE as a single-agent. Of the 63 patients, 4 achieved partial responses, 3 achieved minor responses, and 16 demonstrated stabilization of previously progressive disease for a minimum of 3 months. ONCONASE was generally well-tolerated; only 8% (5 patients) had their treatment terminated due to adverse reactions.

"Interim results from treatment with ONCONASE in patients with malignant mesothelioma have been encouraging," stated Dr. Robert Taub, Professor of Clinical Medicine and Director of the Soft Tissue Program at Columbia-Presbyterian Medical Center in New York City. "Most patients with this disease do not respond to traditional chemotherapy. Patients, including those who have failed other cancer therapies, have benefited from treatment with ONCONASE. We are eager to begin the Phase III trial in this indication."

Due to the promising interim results from the Phase II study, a controlled, prospectively randomized Phase III trial comparing ONCONASE vs. doxorubicin (a chemotherapeutic agent which is widely-used in this patient population) is being initiated at more than 17 treatment centers across the United States in patients with malignant mesothelioma. The objectives of this trial are to compare the safety, efficacy (including survival), and quality of life for the two treatments.

ALFACELL Corp., the world leader in the development of ribonucleases (RNases) for therapeutic applications, is currently testing ONCONASE, an investigational antitumor agent against solid tumors in various clinical trials. ONCONASE is the smallest known member of the superfamily of pancreatic RNases, and is the only cytotoxic RNase currently in clinical trials. Additionally, it has demonstrated, both in vitro and in vivo, an ability to overcome multiple drug resistance (MDR) in various tumor models. MDR is thought to be responsible for approximately 90% of chemotherapy failures. Alfacell is currently conducting multi-center Phase I, II, and III clinical trials of ONCONASE against a number of solid tumors, including pancreatic adenocarcinoma, malignant mesothelioma, advanced renal cell carcinoma, and prostate cancer.

ALFACELL, a biopharmaceutical company located in Bloomfield, is engaged primarily in the research and development of novel ribonuclease enzymes for various therapeutic applications. The Company's common stock is traded on NASDAQ under the symbol "ACEL".

For more information concerning participation in the Phase III trial in malignant mesothelioma patients, please call Diane Scudiery, Clinical Research Department, at 201-748-8082 or email: [e-mail] .

CONTACT: Alfacell Corporation

Donna Brasko, 201/748-8082