AZ firms up immuno-oncology imaging deal with ImaginAb

AstraZeneca has expanded its alliance with ImaginAb, an imaging specialist developing imaging agents to increase the efficacy and response rate with cancer immunotherapies.

AZ was one of three drugmakers that got on board with ImaginAb’s CD8 ImmunoPET technology last year, along with Pfizer and Takeda, and is the first to elevate the partnership to a full-blown licensing deal.

California-based ImaginAb is developing a pipeline of imaging agents based on monoclonal antibody fragments – or ‘minibodies’ – that are labelled with radioisotope tracers and can be detected using PET imaging.

The minibodies are inert in the body but can be used monitor immune activity, such as the infiltration of CD8-positive lymphocytes into tumours before and after immuno-oncology drugs are administered.

ImaginAb’s lead CD8 ImmunoPET – called 89ZrCD8PET – is in phase 2 testing to establish whether it can be used to when and where in the human body an immune response is mounted against cancer cells in real time, while also removing the need for invasive biopsies.

The biotech’s near-term business model is to license the technology on a non-exclusive basis to other companies for use in the clinical development of cancer immunotherapies, and a little further out hopes to use it to develop diagnostics for clinical use.

AZ will deploy ImaginAb’s CD8 imaging for patient selection and monitoring in clinical trials across multiple types of cancer in Europe and North America, according to the two companies.

The drugmaker already has one immuno-oncology drug on the market – PD-L1 inhibitor Imfinzi (durvalumab) which made almost $1.5 billion in sales last year – and is also developing a number of others.

Its pipeline includes CTLA4 inhibitor tremelimumab, which has suffered a number of setbacks in late-stage testing for a number of cancer types, and anti-NKG2A antibody monalizumab in phase 2.

In theory at least, immunodiagnostics could be used to select patients into trials who stand the best chance of getting a benefit from a drug treatment.

The financial terms of the AZ deal haven’t been revealed, but include license fees and “other contingent payments,” according to a spokesman.

“Under the new agreement, ImaginAb will provide AstraZeneca with clinical doses of ImaginAb’s CD8 ImmunoPET minibody, as well as technical support, to…trials involving novel immunotherapies,” said the US biotech’s chief executive Ian Wilson.

“The CD8 PET tracer…is a powerful diagnostic approach for measuring non-invasively the effect of immunotherapies, which we believe will ultimately be used to predict therapeutic efficacy,” he added.