Stem Cell Company Shares Jump Following Revolutionary Cancer Operation Breakthrough.

Pluristem, whose shares trade at a company valuation of $139 million, develop drugs based on placental stem cells.

Shares in stem cell research companies rose sharply on Friday following the news of a scientific breakthrough at Karolinska University Hospital in Stockholm, Sweden: Pluristem Therapeutics stock jumped 6.7% on triple its average turnover when the successful transplantation of a synthetically engineered stem cell-based windpipe into a cancer patient at the hospital was announced.

Despite aggressive radiation therapy, the tumor blocking the 36-year-old patient's trachea had grown to 6cm. in length and was reaching the main bronchus. A suitable windpipe donor couldn't be found and the transplantation of the synthetic organ became the patient's only remaining option.

Tomer Neuberg

The operation was led by Prof. Paolo Macchiarini of the hospital, and the surgical team included Prof. Alexander Seifalian of University College in London. Researchers grew the synthetic windpipe on a nanocomposite tracheal scaffold seeded with the patient's own stem cells in a bioreactor for just two days.

Because the stem cells used for growing the synthetic windpipe were the patient's own, there was no rejection of the transplant and the patient was not required to take immunosuppressive drugs. The doctors subsequently declared the patient free from cancer and projected a normal life expectancy.

Pluristem, whose shares trade on NASDAQ at a company valuation of $139 million, after gaining 132% since the beginning of this year, develops drugs based on placental stem cells. The company's unique method involves injecting stem cells into the patient in two doses four months apart, without genetic matching or subduing the patient's immune system to prevent rejection.

In January, Pluristem received approval from the U.S. Food and Drug Administration and the European Medicines Agency to skip second-phase clinical testing of its flagship PLX-PAD treatment for limb ischemia from peripheral artery disease, and to proceed directly to decisive third-phase trials. In the United States, 2.7 million patients suffer from this disease, with treatments totaling $10 billion annually.

Pluristem signed an agreement last month with U.S.-based United Therapeutics, which deals with treatments for pulmonary patients. Under the agreement, United Therapeutics will use Pluristem's PLX placental stem cells to develop products for treating pulmonary hypertension patients. Pluristem will receive a $7 million advance on closing the deal and additional payments totaling $48 million based on achieving specified milestones. Pluristem will also be compensated for expenses totaling between $20 million and $45 million in connection with developing the product, clinical trials and marketing.

Shares of Mesoblast, an Australian company developing drugs for leukemia based on embryonic stem cells, were also boosted by the Karolinska University Hospital breakthrough, rising 5.4% to a company valuation of $2.7 billion. Cephalon, a U.S. biopharmaceutical company holding a 19.9% stake in Mesoblast, is being acquired by Teva Pharmaceuticals for $6.8 billion.