International Stem Cell Corp., a Carlsbad-based biotech company developing stem cell therapies and biomedical products, announced that the U. S. Food and Drug Administration has cleared the company’s human parthenogenetic stem cells line for investigational clinical use.

Human embryonic stem cells typically come from fertilized eggs. In 2007, however, scientists at International Stem Cell Corp. (ISCO) reported the first successful creation of human stem cell lines from unfertilized eggs, according to Scientific American.

They used a process called parthenogenesis, in which researchers use chemicals to induce the egg to begin developing as if it had been fertilized. The egg — called a parthenote — behaves just like an embryo in the early stages of division. Because it contains no genetic material from a father, however, it cannot develop into a viable fetus. Just like embryonic stem cells, parthenogenetic stem cells can be coaxed to grow into different kinds of human cells or tissue, ready to be transplanted into diseased areas of the body.

"Many stem cell lines can never be used to develop commercial therapeutic products because they don't meet the FDA's ethical and quality standards,” said Ruslan Semechkin, ISCO’s chief scientific officer. “With this clearance from the FDA, based on the safety of our cells and quality of our manufacturing processes, the company has removed any uncertainty in the potential clinical use of human parthenogenetic stem cells.

"Not only does this increase the chance that our regulatory submission for the treatment of Parkinson's disease, which we will be submitting before the end of the year, will be approved, but it also means that our human parthenogenetic stem cells can serve as the basis for investigational clinical studies for other indications, for example stroke or traumatic brain injury."

To be approved by the FDA for use in human trials and commercial therapeutic products, stem cells must be grown under what's known as good manufacturing practice (GMP) conditions. GMP standards require that each batch of cells is grown in identical, repeatable conditions, ensuring that they have the same properties, and each person receiving a stem cell therapy would be getting an equivalent treatment. According to ISCO, achieving this level of consistency is difficult and requires knowing the exact identity and quantity of every component of the media that the cells grow in and characterizing cell batches extremely precisely, as well as rigorous quality control and assurance.

ISCO (OTCQB: ISCO) will use its own GMP facilities in Oceanside to produce the cells in preparation for the first clinical trial.