By Debbie Strickland

A new cell-culturing device could make bone marrow extractions less invasive while reducing side effects, suggest results from a six-patient study at the Loyola University Medical Center.

The Aastrom CPS (Cell Production System) grew bone marrow cells from a small amount of material outside the patient's body, retaining the stem and other key immune cells needed to restore tissues destroyed by aggressive cancer treatments. The device, designed for widespread medical use, is the first of its kind to succeed, the company said.

"The validation of our technology is an important milestone," said R. Douglas Armstrong, president and CEO of the Ann Arbor, Mich.-based biotech firm.

The company's shares (NASDAQ:ASTM) closed Tuesday at $4.125, up $0.125.

Aastrom raised $21 million in an initial public offering earlier this year and has reserves that can last 18 to 20 months, Armstrong said.

The desk-sized Aastrom CPS uses closed-system, disposable cassettes containing a medium to grow therapeutic cells, using a patented process for stem cell expansion. Armstrong said the machine is the first commercial technology to enable patient-specific production of therapeutic human stem cells at clinical sites.

Aastrom is planning multicenter pivotal trials of the CPS to support a pre-market approval application for marketing clearance. The device would be marketed -- as early as late 1999 or early 2000 in the U.S. -- by Lakewood, Colo.-based COBE BCT, a subsidiary of Sweden's Gambro AB and owner of a 24 percent equity stake in Aastrom. The CPS may be approved earlier in Europe, where a trial is under way.

Pricing has yet to be determined. "It will be very cost effective," he said. "We have designed it to be operated by any standard medical technician."

The commercialization of the CPS would mark a financial turning point for Aastrom, said analyst David Stone, managing director at the Boston office of New York-based Cowen & Co. Stone projects annual sales of $140 million by 2000, assuming a market penetration of just under 20 percent. That's the same year he expects the company to become profitable, with about $1 per share net income.

"The Cell Production System is exciting as a platform technology," Stone said, "because it's the first method of growing cells that's really user-friendly. It's like a PC for cell cultures."

He said the technology is an "enabling" one, of significance to the biotechnology industry as a whole. It could, for example, make the clinical use of ex vivo gene therapies and umbilical stem cells practical. Other applications the company is exploring include disease-specific T cells, chondrocytes (for cartilage restoration), neuronal cells and keratinocytes.

The director of Loyola's Bone Marrow Transplant Program in Chicago, Patrick Stiff, presented results from the initial bone-marrow study Tuesday at the American Society of Clinical Oncology's annual meeting, in Denver.

"The promising results of this study suggest that use of the Aastrom CPS to produce therapeutic stem cells from bone marrow and other sources -- including umbilical cord blood -- may make it possible to convert stem cell collections into a brief outpatient procedure, while lessening the costs and risks associated with transplant care," Stiff said.

Each year, approximately 1 million Americans undergo radiotherapy and chemotherapy treatments. At high doses, and when used in combination with each other, these cancer-killing treatments also destroy the stem cells in a patient's bone marrow. These cells can be restored by infusion of stem cells collected from the patient or donor before cancer treatment is administered.

The Loyola study enrolled six patients with advanced breast cancer who had undergone high-dose stem-cell ablative chemotherapy. A small amount of bone marrow (approximately 38 cc) was collected from each patient for the procedure. By contrast, conventional bone marrow and peripheral blood stem cells (PBSC) transplant procedures require a minimum of 1,000 cc, or drug treatments followed by large-volume apheresis completed over several days.

"Engraftment of the stem cells was successfully achieved in all patients studied, in a time frame comparable with that of conventional ablative bone marrow therapy," Stiff said.

Patients recovered their white blood cell counts within a median of seven days; neutrophil counts, 16 days; and platelet counts, 23 days. Aastrom's CPS-mediated production yielded a full dose of cells after 12 days of culture.

The technology yields two clinical benefits:

* Reduction or elimination of tumor contamination compared to conventional stem cell transplant procedures. Past studies have found that undetected tumor cells infused with the current standard procedures of transplanting bone marrow or PBSCs can contribute to a recurrence of cancer.

* Very low incidence of febrile neutropenia, a common side effect of stem cell transplant procedures.

Current procedures for stem cell collection are normally lengthy and invasive: Obtaining a large volume of bone marrow is an inpatient procedure requiring up to 16 hours and 103 needle sticks. Drug-enhanced blood removal is an outpatient procedure but can take up to 39 hours and 22 needle sticks.

The CPS procedure, by contrast, takes one outpatient visit of less than two hours. *