MedImmune looks to 'next generation biologics' with $200m ADC investment

AstraZeneca has become the latest company to invest in antibody-drug conjugate (ADC) technology with the acquisition of Spirogen for $200m (€148m).

The deal - which could be worth up to $440m depending on milestones - sees the Pharma Giant, through its biologics arm MedImmune, acquire Spirogen and its proprietary pyrrolobenzodiazepine (PBD) platform just days after Roche and Novartis announced plans to invest in similar technologies.

A number of companies had been interested in the platform, but MedImmune - who, along with global equity company Auven Therapeutics  has also invested in Swiss firm ADC Therapeutics - was the “ideal partner,” according to Spirogen co-founder and Chairman Stephen Evans-Freke.

He told in-Pharmatechnologist.com MedImmune “has tremendous ADC know-how, a long history in oncology and a very strong strategic focus. Most importantly [MedImmune] is determined to be a major force in the future of ADCs.”

ADCs discriminate between diseased cells and normal tissue and are a key focus for the industry in targeting cancers. They consist of a monocolonal antibody, diabody or ScV fragment that displays a high binding affinity to a cancer specific target antigen, a highly potent cytotoxic agent (commonly known as ‘warheads’) and a ‘linker’ designed to allow ADCs to remain inactive when in the blood.

Evans-Freke, who is also Managing General Partner of Auven, told us Spirogen’s technology was originally developed to combat the emerging drug resistance found in chemotherapy. However, when the platform was investigated further it turned out to have a unique effect for ADCs, with the warheads having higher efficacy compared with a number of other platforms available.

Next Generation

With so few ADCs achieving regulatory approval - in the US, just Genetech’s Kadcyla and Seattle Genetic’s Adcetris currently available - we asked Evans-Freke what has sparked the recent upsurge in ADC investments (on top of Roche and Novartis, Carbogen Amcis and SAFC have invested in the last few weeks).

“The current generation of biologics is worth over $30bn,” he said with the next generation having the potential to make huge improvements to patients. As an example, he said a patient with breast cancer’s life expectancy is improved by six month on average with the Genetech monoclonal antibody Herceptin, whilst the ADC equivalent - Kadcyla - more than doubles this.

“ADCs are the future for the sector of cancer biologics,” he continued, adding: “I believe we’re going to see major growth in the next decade.”