Privately held Antolrx Inc. said Pfizer Inc. has exercised an option to exclusively license an immune tolerance therapy from the Cambridge, Mass.-based company's type 1 diabetes (T1D) program, triggering an up-front payment of undisclosed value and potential milestones of up to $51 million, Antolrx's co-founder, president and CEO, Mark Carthy, told BioWorld.

Pfizer, which will be responsible for further development and potential commercialization of the candidate, previously backed a $4 million series A financing of Antolrx alongside Orion Equity Partners LLC and JDRF in mid-2016.

Michael Vincent, chief scientific officer for Pfizer's inflammation and immunology unit, said his company sees Antolrx's approach "to re-educate the immune response as one potentially promising strategy to achieve that goal for patients." The New York-based big pharma, which on Monday priced a $5 billion debt offering, has also highlighted immunological tolerance — normal physiological processes to prevent activation of the immune system by self-antigens — as a key element of its approach to immunology and inflammation R&D.

Antolrx is developing antigen-specific therapies leveraging immune tolerance induction for the potential treatment of several inflammatory and autoimmune diseases. Its approach builds on the immunoregulatory research of Francisco Quintana, a professor of neurology at Brigham and Women's Hospital in Boston, as well as the company's scientific founder and chief scientific advisor.

In autoimmune disease, immune cells improperly target self-antigens, destroying various cells and even organs. Antolrx is taking advantage of research showing that those same immune cells can be re-tolerized or re-programmed, turning them into regulatory T cells by exposing them to self-antigens, usually in the lymph nodes or spleen, Antolrx scientist Jessica Kenison-White told BioWorld. In T1D, the body's immune system destroys cells in the pancreas that produce insulin, meaning the body produces little to no insulin to regulate blood sugar and get energy from food.

Each of the Antolrx's nanotechnology-enabled formulations co-delivers both a self-antigen and an aryl hydrocarbon receptor (AHR) activator to induce immune tolerance and suppress autoimmune disease. Once taken up by dendritic cells, AHR signaling is activated and the self-antigen is presented to T cells, leading to the induction of antigen-specific tolerance.

Antolrx is working to advance pipeline programs for rheumatoid arthritis, celiac disease and five other autoimmune indications.

The antigen employed by the company's T1D candidate is an insulin antigen selected because insulin antibodies are commonly found in people with the condition, with their presence correlating with progression to disease, said Kenison-White. Catching the disease early, before too much damage has been done to beta cells and the pancreas, could potentially enable reversing the course of disease and preventing further progression, she said.

Prior to Pfizer's option to exercise, Antolrx was planning to declare a candidate from the T1D program in the first quarter of 2020, followed by work on CMC and formal preclinical studies later that year and a mid-2021 investigational new drug filing. However, now that Pfizer is in the driver's seat, the timeline could change.

"There is an urgent need for disease-modifying type 1 diabetes immunotherapies to slow down the autoimmune process and delay or block progression to symptomatic insulin-dependent diabetes," said JDRF President and CEO Derek Rapp.