Pfenex & Arcellx Announce Development, Evaluation & License Agreement

Pfenex Inc. and Arcellx, Inc. recently announced a Development, Evaluation, and License agreement under which Arcellx gains access to the proprietary Pfenex Expression Technology platform to advance multiple proprietary sparX proteins that activate, silence, and reprogram Antigen-Receptor Complex T cell based therapies. Pfenex has successfully completed expression screening and process development activities for the first sparX program. Technology transfer of the program to a cGMP manufacturing facility is underway.  The success of the first program has encouraged both parties to initiate a second sparX program, both programs are focused on the treatment of hematologic malignancies.

Under the terms of the agreement, Pfenex is eligible to receive development funding in addition to development, regulatory and commercial milestones ranging from $2.6 million up to $18 million for each product incorporating a SparX protein expressed using the Pfenex Expression Technology as well as royalties on worldwide sales of any such products.

“Our collaboration with Arcellx fits our strategy of leveraging the Pfenex protein production platform to advance our products and those of our collaborators. Pfenex’s success with the first sparX program further validates the versatility of our proprietary protein expression platform and the quality of our development capabilities. We look forward to collaborating with Arcellx through the combination of our respective platforms in support of developing new therapies for patients in need.” said Eef Schimmelpennink, Chief Executive Officer of Pfenex.

“The uniquely efficient protein expression technologies and process expertise developed by Pfenex have been critical in accelerating development of our first sparX program,” said David Hilbert, Chief Executive Officer of Arcellx. “Our continued development of new sparX programs provides the basis for a forward looking Pfenex collaboration involving multiple sparX proteins with the potential to revolutionize immune cell therapies.”

Pfenex is a clinical-stage development and licensing biotechnology company focused on leveraging its Pfenex Expression Technology to develop and improve protein therapies for unmet patient needs. Using the patented Pfēnex Expression Technology platform, Pfenex has created an advanced pipeline of therapeutic equivalents, vaccines, biologics and biosimilars. Pfenex also uses its Pfenex Expression Technology platform to produce CRM197, a diphtheria toxoid carrier protein used in prophylactic and therapeutic vaccines. Pfenex’s lead product candidate is PF708, a therapeutic equivalent candidate to Forteo (teriparatide) for the treatment of osteoporosis. In addition, Pfenex is developing hematology/oncology products, including PF743, a recombinant crisantaspase, and PF745, a recombinant crisantaspase with half-life extension technology, in collaboration with Jazz Pharmaceuticals.

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Arcellx is a privately held development-stage company devoted to providing patients with superior immune cell therapies through scientific innovation, accelerated development, and responsible patient care.  Our lead programs target cancer with first-in-class adaptive immune cells called Antigen-Receptor Complex T cells (ARC-T) that are readily silenced, activated, and reprogrammed by a sparX protein therapeutic.  Although our initial clinical focus is cancer therapy, we are committed to extending our therapies across a broad spectrum of human disease.