First licensee near for Crucell's STAR?

In a joint evaluation programme that is funded by Genentech, the companies are investigating whether the technology can increase the production yields of Genentech's proprietary systems.

The STAR technology is based on the concept of epigenetics - the study of cellular factors (usually DNA and protein factors) that are involved in the regulation of gene expression.

In man, 80 to 90 per cent of genes are switched off, or silenced, because they code for proteins that are not essential for the functioning of cells. In fact, genes are silenced by default in cells, and those that need to remain active only do so because of the action of regulatory sequences.

This means that when cells are transformed with the DNA sequence required to make a protein, "the chances that the gene is integrated into a silent part of the genome are large,"​ Prof Arie Otte, ChromaGenics founder, told In-PharmaTechnologist.com​. The solution is to use regulatory sequences - known as STAR elements - on either side of the protein-coding sequence (transgene), to create a non-silent portion of the genome.

The technology is thought to be particularly useful for the production of recombinant human antibodies and proteins. It has a potentially broad application and is effective for production of antibodies and proteins on mammalian cell lines such as Crucell's own PER.C6 cell line and the widely used Chinese hamster ovary (CHO) line.

The first phase of Genentech's programme, now completed, evaluated production yields in screening assays. Based on these results, the biotechnology major has decided to enter into a second phase, in which it will test the effectiveness of STAR under scaled-down production conditions.

If the final phase of the evaluation proves successful, Genentech has an option to sign a non-exclusive STAR license agreement, which will be the first license for the technology since the acquisition of ChromaGenics.