Astellas Builds Vaccine Portfolio With Affinivax Pneumococcal Candidate
Executive Summary
Despite one recent setback, Astellas is continuing to expand its vaccines business through a new global deal for Affinivax's lead MAPS pneumococcal product, in a move that builds on earlier research links between the companies.
Astellas Pharma Inc. is paying $10m upfront to acquire exclusive worldwide rights to develop and commercialize a novel pneumococcal disease vaccine developed by Affinivax Inc. using the US venture's proprietary Multiple Antigen Presenting System (MAPS) technology.
The candidate, used to prevent infections caused by the Streptococcus pneumoniae bacterium including pneumonia, meningitis, and sepsis, is Affinivax's lead pipeline project and is still at the preclinical stage, but has shown promising signs of activity.
As part of the new agreement, Astellas will lead and fund in full a planned global clinical development program, with Affinivax eligible for further undisclosed milestone payments related to development, approvals in targeted indications, and commercial sales, plus tiered royalties.
Astellas said there would be no financial impact from the deal on its existing guidance for the fiscal year ending March 31.
Existing Links
The deal builds on existing links forged in September 2015 between Affinivax and Astellas's vaccines R&D partner ClearPath Development Company LLC to research prophylactic MAPS vaccines for the prevention of bacterial nosocomial infections.
ClearPath, with support from Astellas, set up a dedicated venture, Nosocomial Vaccine Corp., in that year to develop products in this area.
ClearPath and its parent RRD International have been helping Astellas identify and develop vaccine candidates, which led to the Japanese firm acquiring global rights in 2013 to Mymetics Corp.'s preclinical respiratory syncytical virus (RSV) vaccine.
This product is being developed through RSV Corp, another company formed with ClearPath's support and an Astellas minority investment in the same year.
MAPS Benefits
The MAPS platform, developed by Affinivax and for which intellectual property was licensed from the Boston Children's Hospital in the US, enables the high-affinity binding of protective polysaccharides and proteins in a single vaccine.
Standard vaccine conjugation is a complex process designed to induce protective antibody response to the polysaccharide antigen only, with the protein antigen acting mainly as a carrier.
By contrast, MAPS makes use of the strong non-covalent bonding of biotin to its binding protein rhizavidin to form a stable complex. This enables the incorporation of multiple antigens, potentially allowing broader disease-protective immune responses than conventional conjugate vaccines.
MAPS vaccines then elicit immunity by triggering an immune response to both their bound polysaccharide and protein antigens, and in the case of the pneumococcal vaccine the approach should allow protection against a wider range of serotypes.
MAPS vaccines also elicit a T-cell response that reduces the nasopharyngeal colonization that leads to initial disease transmission, and may be able to be produced at a lower cost than existing S pneumoniae vaccines.
Affinivax notes that preclinical data show that the prototype pneumococcal vaccine induces a "robust, multipronged immune response" comparable to current standard vaccines, plus additional protective antibody and Th1 and Th17 responses.
Funding, Plans
Cambridge, Massachusetts-based Affinivax received a $4m founding investment from the Bill & Melinda Gates Foundation in October 2014, and a further $2.5m allocation from the foundation around a year ago.
Besides the pneumococcal and nosocomial areas, the venture is also looking at applying the MAPS technology to other areas including Salmonella typhi and Staphylococcus aureus.
For Astellas, while vaccines are not being positioned as a core area, the company - in common with some other Japanese majors including Takeda Pharmaceutical Co. Ltd. and Daiichi Sankyo Co. Ltd. - is developing its vaccine franchise. Astellas's current mid-term strategic plan for 2015-17 specifically includes the pursuit of new areas of technology, including novel vaccines.
The company is already conducting clinical trials with ASP0113 (VCL-CB01), a DNA vaccine licensed from Vical Inc. for cytomegalovirus reactivation in recipients of hematopoietic cell transplants (Phase III) and solid organ transplants (Phase II).
Other Phase I work is underway with Immunomic Therapeutics Inc. on ASP4070, a LAMP-vax DNA vaccine causal therapy for Japanese red cedar pollinosis. The two companies entered an alliance in 2015 for Immunomic's pipeline of DNA vaccines against human allergies. (Also see "Allergy Deal Boosts Astellas's Pipeline, Allows Immunomic Refocus" - Scrip, 14 Oct, 2015.)
Setback
Astellas recently had a setback for its most advanced pipeline vaccine however, when it exercised a right to terminate an agreement with Japanese vaccines venture UMN Pharma Inc.
The two companies had been co-developing two recombinant cell-cultured influenza vaccines, ASP7374 (UMN-0502) for seasonal flu prophylaxis (filed in Japan) and ASP7373 (UMN-0501) for H5N1 prophylaxis (Phase II in Japan).
Astellas has returned rights following discussions with Japan's regulator, the PMDA, which suggested ASP7374 was unlikely to be approved with the current data package. (Also see "Deal Watch: J.P. Morgan Brings Continued Brisk Pace Of Transactions" - Scrip, 12 Jan, 2017.)
From the editors of PharmAsia News.