Many rare diseases are caused by enzyme deficiencies resulting from a genetic defect. Until now, these diseases have been treated with enzyme replacement therapy designed to break down toxic metabolites that accumulate in the body due to the missing or deficient enzyme. The body sometimes recognizes these therapeutics enzymes as foreign and attempts to degrade them before they can do their job. Current therapeutic approaches are often ineffective, poorly tolerated and require frequent infusions.
RCTTM product candidates are engineered to express the necessary enzymes within each cell, shielding them from the immune system. As RCTs circulate, they are expected to break down the toxic metabolites in the blood stream that have accumulated. Compared to current therapeutic approaches, RCTs may have a longer and more sustained treatment effect given the 120-day circulating time of red blood cells and may avoid immune-driven adverse events, including formation of neutralizing antibodies to the therapeutic enzyme, which often result in a reduction in efficacy. We expect RCTs to provide a more efficacious treatment option to patients.
Our lead programs target rare enzyme deficiencies where no available treatment options exist or current treatments may be improved. Initially, we are focusing our efforts on creating RCTs for the potential treatment of phenylketonuria, chronic refractory gout and homocystinuria.
Recent treatment advances have focused on activating the immune system against cancer. Despite this progress, existing immunotherapies are effective in a relatively small number of patients and types of cancer. Furthermore, even when therapies are initially effective, the disease eventually no longer responds to treatment and progresses.
RCTTM product candidates can be engineered to co-express combinations of co-stimulatory molecules on their cell surface to directly engage both the adaptive immune system and the innate immune system. By stimulating both powerful arms of the immune system, RCTs may be better able to destroy cancer cells to improve anti-tumor activity and overcome resistance to immunotherapy.
We believe RCTs will have broad therapeutic application across a range of both solid tumors and hematological cancers.
Autoimmune diseases are the result of a hyperactive immune response that mistakes healthy tissue as foreign. Over time, these attacks on healthy cells lead to disease. Current therapies are generally administered on a lifelong basis, initially work for only a subset of patients, tend to lose effectiveness over time and are often associated with serious side effects, including opportunistic infections, lymphoma and, in some cases, severe or fatal reactions.
RCTs can be engineered to express disease-causing antigens on their cell surface. When these RCTs are processed by the reticuloendothelial system, these antigens are expected to be re-presented to the immune system and thereby retrain the body to no longer see these self-antigens as foreign. The resulting restoration or induction of immune tolerance may lead to more effective treatments—potentially even cures—for certain autoimmune diseases, such as pemphigus vulgaris and Type I diabetes, among others.