Leukemia cure could be on the way, says med-tech firm Biosight

Biosight, an Israeli pharmaceutical development company that is working on a cure for leukemia, this week closed an investment of $13 million led by pharmaceutical investment firm Arkin Holdings, run by pharma mogul Mori Arkin, and US-based venture firm Primera Capital. The money will be used to fund an advanced phase study of the company’s lead product, Astarabine, for the treatment of AML — acute myeloid leukemia, one of the two most common forms of the disease.

According to the investment terms, Arkin Holdings and Primera Capital will invest $5 million each, and additional $3 million will be invested by existing shareholders. The investment will be made in two steps, the first immediate, and the second expected in the course of the next year upon completion of several studies and milestones.

Astarabine is a special form of a compound called cytarabine that contains an amino acid harmful to leukemia cells but not to normal cells. Leukemia cells depend on an amino acid called aspargine, but they cannot synthesize it themselves, according to Dr. Ruth Ben Yakar, CEO of BioSight; as a result, they “steal” it where they can, from within the bloodstream. “We set up a molecular structure that leukemia cells recognize as being associated with aspargine, which they need,” said Bar Yakar. “But instead we fill it with Astarabine, which kills them. Thus, using this trojan horse trick, we are able to destroy the cancerous cells while preserving the healthy ones.”

It’s stealthy enough to fool even the “smartest” cancer cells, said Ben Yakar. “Our interim results in a major study of patients with leukemia shows that that our system yields the maximum efficiency from chemo, with a minimum of toxicity. Our method of using chemo does not cause brain damage or weaken blood cells,” with all its attendant phenomena, such as lethargy, loss of hair, etc.

This “trojan horse” chemo technology doesn’t only work for leukemia patients, said Ben Yakar. “We believe it will be effective in many other kinds of cancer as well. It’s a matter of finding the amino acid that a specific cancer is allergic to, and packaging it in a structure that the cancer cell thinks contains material that strengthens it, while in reality it contains material that destroys it.”

BioSight is currently completing a Phase I/IIa clinical trial to evaluate the safety and efficacy of Astarabine as a therapy for AML and ALL (relapsed/refractory Acute Lymphoblastic Leukemia, another common form of the disease) that was conducted at Rambam Hospital in Haifa under the supervision of Dr. Tsila Zuckerman. The results obtained to date indicate a good safety profile with no significant drug-related side effects, including in 80-and 90-year-old patients, said the company. In addition, Astarabine treatment achieved “high response rates” in newly diagnosed AML/ALL and secondary AML patients deemed unfit by doctors for conventional chemotherapy.

While further tests are needed, Ben Yakar is very optimistic that the technology – which, she said, could be applied to other cancers as well, will receive recognition as a breakthrough therapy, able to treat patients who have no other medical recourse. “We are excited with the results obtained to date with treatment of AML and ALL patients with Astarabine,” said Ben Yakar. “These patients would have otherwise had very limited treatment options. We are optimistic that Astarabine could bring real hope to many patients and an answer to unmet needs in the treatment of hematologic malignancies.”