AstraZeneca oncology portfolio strengthened as MedImmune acquisition of Spirogen boosts antibody-drug conjugate capability

AstraZeneca today announced that MedImmune, its global biologics research and development arm, has acquired Spirogen, a privately-held biotech company focused on antibody-drug conjugate technology for use in oncology.

MedImmune has also entered into a collaboration agreement with ADC Therapeutics to jointly develop two of ADC Therapeutics’ antibody-drug conjugate programmes in preclinical development. MedImmune will also make an equity investment in ADC Therapeutics, which has an existing licensing agreement with Spirogen.

MedImmune will acquire 100 per cent of Spirogen’s shares for an initial consideration of $200 million and deferred consideration of up to $240 million based on reaching predetermined development milestones. Existing out-licensing agreements and associated revenue streams are excluded from this acquisition.

MedImmune will also pay $20 million for an equity investment in ADC Therapeutics, which will be matched by Auven Therapeutics, the majority shareholder in both ADC Therapeutics and Spirogen. The collaboration agreement will include an upfront payment with predetermined development milestones for two programmes from a defined list and a cost- and profit-sharing arrangement with MedImmune representing the majority share. ADC Therapeutics will also have the option to co-promote one of the products in the US.

Antibody-drug conjugates are a clinically-validated cancer drug technology that offers both high potency and selective targeting of cancer cells. Spirogen’s proprietary pyrrolobenzodiazepine (PBD) technology attaches highly potent cytotoxic agents, or ‘warheads’ to specific cancer-targeting antibodies using biodegradable ‘linkers’. This targeting optimises the delivery of the cancer drug to the tumour cells only and provides the greatest degree of tumour killing while minimising the toxicity to the patient.

“Antibody-drug conjugates are ground-breaking technologies with the potential for directly targeting many types of cancer tumours while safeguarding healthy cells. The cutting-edge technologies developed by Spirogen and ADC Therapeutics complement MedImmune’s innovative antibody engineering capabilities, enabling us to accelerate antibody-drug conjugates into the clinic,” said Dr. Bahija Jallal, Executive Vice President, MedImmune.

Oncology is a core therapy area for AstraZeneca spanning both small molecule and biologics research and development. MedImmune is developing a comprehensive portfolio with an emphasis on two key areas in oncology development: antibody-drug conjugates and immune-mediated cancer therapy, which aims to harness the power of the patient’s own immune system to fight cancer. Together, immune-mediated cancer therapies and antibody-drug conjugates have the potential to treat cancer in a way that current therapies are unable to do.

“This deal reflects the very significant progress made by our scientists, most notably over the last two years, as we have applied our warhead and linker technologies to the development of highly potent and specific antibody-drug conjugates,” said Dr. Chris Martin, Chief Executive Officer, Spirogen. “We believe that pyrrolobenzodiazepine-armed antibody-drug conjugates will emerge as a critical component in the next generation of cancer biologics with the potential to make a difference for oncologists and their patients. We look forward to combining our world-class capabilities in this area with MedImmune’s ability to develop this exciting class of oncology drugs.”