Although our technology is applicable across a wide array of immune disorders, we have chosen to focus initially on asthma, pulmonary arterial hypertension, rheumatoid arthritis (RA), and psoriasis. This choice was influenced by the technological fit, predictive value of available animal models, magnitude of unmet medical need, and commercial attractiveness.

Asthma

Asthma is a chronic and complicated inflammatory disorder in which mast cells, eosinophils, and T lymphocytes infiltrate small airways. Asthmatics have recurrent episodes of wheezing, shortness of breath, chest tightness, and cough. Current therapies aim to alleviate acute symptoms and block inflammation.
Approximately 7% of Americans suffer from asthma; the retail prescription market in the U.S. in 2005, comprised of bronchodilators, leukotriene inhibitors, and inhaled steroids, was approximately $13 billion. New agents that provide greater efficacy, tolerability, and convenience are commercially attractive.

Pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a syndrome where restricted blood flow through the pulmonary artery can lead to pulmonary artery resistance and right-sided heart failure. Patients with PAH often have a substantial decrease in their ability to breathe, exercise, and function normally.
About 150,000 Americans have PAH. New agents that improve morbidity and mortality are commercially attractive.

Rheumatoid arthritis

RA is a chronic inflammatory disease characterized by progressive joint destruction. Although the cause of RA remains unclear, most scientists view RA as an autoimmune disease in which infiltration of synovial tissue by lymphocytes and macrophages leads to cartilage destruction and bone damage.
There are approximately 1.5 million RA patients in the U.S. and 3.6 million patients worldwide. U.S. physicians typically prescribe disease-modifying anti-rheumatic drugs (DMARDs) with the intention to stop or slow disease progression, and anti-inflammatory drugs for symptomatic relief.
Methotrexate, a conventional DMARD, is the most frequently prescribed RA drug, but patients who cannot tolerate methotrexate, or in whom the disease continues to progress, are candidates for injectable biologics. Use of biologics in RA has increased substantially, with worldwide sales over $10 billion.
Although biologics have raised the standard for efficacy of new therapies, there is ample room for new disease-modifying therapies that can deliver greater efficacy, particularly if they are orally available and less expensive. A new, oral drug with an efficacy and tolerability profile similar to or better than biologics should enjoy substantial commercial success.

Psoriasis

Psoriasis is an immune system disorder that affects the skin, and occasionally the eyes and nails; it is a chronic, recurrent disease marked by epidermal proliferation. Patients may experience recurring remissions and exacerbations.
Approximately 5.5 million Americans have psoriasis. Treatment depends on the type of psoriasis, the extent of the disease, the patient’s response, and the effect of the disease on the patient’s lifestyle. No cure exists. All treatments are palliative, and fall in three categories: topical skin care; phototherapy; and medications. The U.S. psoriasis prescription drug market is approximately $4.3 billion.