Polymyalgia Rheumatica
A common autoimmune disease causing widespread muscle pain and stiffness, primarily in adults after age 50.
What is polymyalgia rheumatica?
Polymyalgia rheumatica (PMR) is the most common autoimmune disorder among the elderly. This condition is associated with aches and pains, primarily in the limbs, as well as stiffness in affected areas and a limited range of motion. Approximately 10% of patients with PMR are eventually also diagnosed with giant-cell arteritis (GCA)¹, which can cause sudden blindness, stroke, and aortic aneurysm.
Currently, glucocorticoid (steroid) medicines such as prednisolone are the only approved treatments for this condition. While the efficacy response to steroids is often dramatic, even short-term administration can cause serious toxicity. Therefore, once PMR symptoms are under control, the dose of steroids is gradually decreased. However, many patients subsequently experience a flare, requiring administration once again of higher doses of steroids. Some patients are able to stop taking steroids within a year, but others must continue to take them for the rest of their lives.
Due to chronic administration of steroids, patients with PMR often suffer debilitating side effects including poor glucose control (diabetes), cardiovascular disease, hypertension, dyslipidemia, weight gain, sleeplessness, osteoporosis (bone loss), glaucoma, thinning of the skin, and bruising, many of which cause higher risk and have a greater quality of life impact in the elderly population affected by PMR.
Affects approximately 200K people in the U.S. per year.²
The need.
Millions of patients with PMR globally must choose between living with the debilitating symptoms of their disease and suffering the severe side effects of their steroid medicine. Many patients accept the former, due to an unwillingness or inability to tolerate chronic steroid use.
The puzzle of how to separate the desirable and undesirable effects of steroids dates back more than 70 years. To date, scientists have been unable to find a widely applicable and accessible solution – but we believe we’ve cracked the code. By modulating how steroids are regulated intracellularly in key organs, we may have found a way to rethink their utility.
PMR patients are in desperate need of a treatment that is safer than current medicines, but equally as effective.
Our product candidate.
SPI-47 is a combination of an HSD-1 inhibitor and a steroid designed to address the key limitations of steroid medicines, with a first therapeutic target of PMR. While the steroid component, prednisolone, provides anti-inflammatory relief, our proprietary HSD-1 inhibitor, SPI-62, is designed to mitigate the steroid’s severe adverse effects. By upending the industry’s understanding of steroid regulation, our therapy has the potential to solve a decades-old puzzle in autoimmune disease treatment.
Dosed identically to today’s steroid medicines.
A recent study demonstrated the ability for an HSD-1 inhibitor to mitigate acute toxicities of prednisolone, without an effect on a marker of immune response.
¹ Narvaez J, Estrada P, Lopez-Vives L, et al. Prevalence of ischemic complications in patients with giant cell arterirtis presenting with apparently isolated polymyalgia rheumatica. Semin Arthritis Rheum. 2015;45:328–33.
² Mayo Clinic.