Boston Life Sciences Initiates Final Preclinical Toxicity Studies for Inosine; Three-Month Animal Studies Needed to Complete IND Stroke Application.

Business Editors/Health/Medical Writers

BOSTON--(BUSINESS WIRE)--Nov. 13, 2003

Boston Life Sciences (NASDAQ: BLSI) announced that the Company had initiated toxicity studies necessary for the filing of the Company's IND for Inosine for the treatment of stroke. These studies are designed to assess the toxicity of Inosine administered via continuous infusion into the lateral ventricle of the brain in both rats and dogs in a manner identical to that proposed in the clinical trials. It is anticipated that results of these studies should be available in approximately 6 months. If successful (i.e. minimal or no dose-related toxicity), the Company expects to be in a position to file its IND in the second quarter of 2004.

BLSI is developing its Central Nervous System (CNS) regenerative agent, Inosine, for the treatment of stroke, spinal cord injury, and traumatic brain injury. In numerous preclinical studies authored by scientists at Harvard Medical School and published in prestigious peer-reviewed journals, Inosine treatment has been shown to result in functional recovery in rats subjected to severe experimental strokes. This functional recovery has also been shown to correlate with extensive "rewiring" of nerve connections in the brain and spinal cord, which presumably compensates for the denervation caused by the stroke. Inosine appears capable of over-riding the inhibitory factors (such as Nogo) that ordinarily restrict this rewiring or axon regeneration in the CNS. Therefore, by itself, Inosine treatment (in animals) produces anatomically-proven axonal regeneration that is quantifiably many-times that observed with any other experimental treatment described in the published literature thus far. To date, Inosine appears (in review of published studies) to be superior to stem-cell treatments and antibodies to Nogo (in spinal cord injury models), both of which are alternative approaches to axonal or nerve regeneration.

"With the initiation of these preclinical toxicity studies, we are in a better position to define the timeline for our IND submission. Though a previously-completed one-month toxicity test revealed no dose-related toxicity, we cannot predict with certainty what the outcome of these studies will be. However, we are hopeful, based on the fact that Inosine is a naturally-occurring small molecule and the demonstrable lack of toxicity seen thus far, that the results of the current studies will permit us to file the IND during the second quarter of 2004," stated Dr. Marc Lanser, President and Chief Scientific Officer of BLSI. "We believe, based on the available published literature, that Inosine treatment represents the most promising of all approaches to achieving functional improvement after stroke," added Dr. Lanser.

Boston Life Sciences, Inc. (BLSI) is a development stage biotechnology company engaged in the research and development of novel therapeutic and diagnostic solutions for central nervous system diseases (CNS) and cancer. BLSI's products in development include: ALTROPANE(R) and FLUORATEC(TM) radioimaging agents for the diagnosis of PD and ADHD; Inosine and AF-1, nerve growth factors for the treatment of acute and chronic CNS disorders; Troponin I, a naturally-occurring anti-angiogenesis factor for the treatment of solid tumors; and novel therapies for the treatment of PD and ADHD.

Statements made in this press release other than statements of historical fact represent forward-looking statements. Such statements include, without limitation, statements regarding expectations or beliefs as to future results or events, such as operating results and financial position, the expected timing and results of clinical trials, discussions with regulatory agencies, schedules of IND, NDA and all other regulatory submissions, the timing of product introductions, the possible approval of products, and the market size and possible advantages of the Company's products. All such forward-looking statements involve substantial risks and uncertainties, and actual results may vary materially from these statements. Factors that may affect future results include: the availability and adequacy of financial resources, the level of operating expenses incurred, the ability to obtain intellectual property protection, delays in the regulatory or development processes, results of scientific data from clinical trials, the outcome of discussions with potential partners, regulatory decisions, market acceptance of the Company's products, and other possible risks and uncertainties that have been noted in reports filed by the Company with the Securities and Exchange Commission, including the Company's Annual Report on Form 10-K.