Hypoparathyroidism study describes high burden of illness
Patients report experiencing symptoms for more than 13 hours a day and 72 percent of patients report experiencing 10 or more symptoms despite taking calcium and vitamin D
BEDMINSTER, N.J.—NPS Pharmaceuticals, Inc., a global biopharmaceutical company focused on pioneering and delivering therapies that transform the lives of patients with rare diseases, today announced that published results from PARADOX—the most comprehensive research to date analyzing the burden of illness of hypoparathyroidism—show a majority of patients with the disorder experience a multitude of physical, emotional and cognitive symptoms that have an impact on both their personal and professional lives. Hypoparathyroidism is a rare endocrine disorder in which the body is unable to produce sufficient levels of parathyroid hormone (PTH). Results from PARADOX, which was led by researchers from the Mayo Clinic and conducted in conjunction with the Hypoparathyroidism Association, were published in the July issue of the peer-reviewed journal Endocrine Practice.
“The results of this landmark research show that patients with hypoparathyroidism often experience symptoms on a daily basis and that a large percentage of patients continue to experience symptoms despite management with large doses of calcium and vitamin D,” said Bart Clarke, M.D., associate professor of medicine at Mayo Clinic and lead researcher for PARADOX. “Findings from PARADOX demonstrate the significant unmet medical need in patients suffering from this debilitating condition.”
NPS has developed Natpara® (rhPTH [1-84]) for the treatment of hypoparathyroidism and submitted its Biologic License Application to the U.S. Food and Drug Administration in October 2013.
PARADOX surveyed 374 people living with hypoparathyroidism. Participants were asked to assess the prevalence and impact of 38 different symptoms of the disease. Until now, there has been limited research exploring the impact of hypoparathyroidism on the lives of patients, and the nature, type and quantity of hypoparathyroidism symptoms have not been previously documented to this extent. NPS Pharma plans to present and publish additional findings from PARADOX at future medical meetings and in peer-reviewed publications.
“At the Hypoparathyroidism Association, we have heard from many patients about the challenges of living with the disorder. The PARADOX findings validate this feedback and also provide us with new insights about the impact of hypoparathyroidism on health, home life and work. We hope that PARADOX can help us all be better advocates for patients living with this rare disorder,” said James Sanders, president of the Hypoparathyroidism Association.
Among all respondents, 72 percent of patients report experiencing 10 or more symptoms despite taking calcium and vitamin D and patients reported that they experience symptoms for an average of more than 13 hours per day. The most commonly reported physical symptoms were fatigue (82 percent), muscle pain/cramping (78 percent), paresthesia (76 percent), tetany (70 percent), joint or bone pain (67 percent) and pain or weakness in the extremities (53 percent). Emotional symptoms commonly reported included anxiety (59 percent) and depression (53 percent). The most common cognitive symptoms were mental lethargy (72 percent), inability to concentrate (65 percent), memory loss (61.5 percent) and sleep disturbances (57 percent).
Findings also suggest that the burden of illness associated with hypoparathyroidism goes beyond clinical symptoms. The current standard of care for the condition is aimed at short-term symptom management with large doses of oral calcium and active vitamin D. The long-term use of this regime may put patients at risk of complications including soft tissue calcification, kidney stones, nephrocalcinosis, hypercalcemia, hypercalciuria and renal failure. Among patients managed with large doses of calcium and vitamin D, 69 percent experienced comorbidities including heart arrhythmias (66 percent) kidney stones (35.5 percent) and bone fractures (16 percent).
Patients also reported visiting an average of six physicians about their condition both before and after their diagnosis and see their managing physician four times per year. On average, 79 percent of patients reported that they required either hospital stays or emergency room admissions due to their hypoparathyroidism.
In addition to assessing the impact of symptoms on patient health, PARADOX also presents findings related to patient attitudes about hypoparathyroidism and its impact on many aspects of daily and family life. More than half of all patients (56 percent) strongly agreed that they felt unprepared to manage their condition at diagnosis. Sixty percent stated that controlling their hypoparathyroidism was harder than they expected.
PARADOX also highlights the impact of hypoparathyroidism on one’s ability to handle daily activities, work, and relationships with family and friends. The vast majority (85 percent) of patients reported that hypoparathyroidism affects their ability to perform household activities, with 62 percent reporting that they experience these challenges on a daily/weekly basis. Among unemployed patients, 72 percent reported that their hypoparathyroidism was the primary cause. In relationships with family and friends, 32 percent reported that their hypoparathyroidism “significantly” affected their ability to socialize, while 35 percent reported that it interfered with intimacy.
The PARADOX research assessed the clinical, social and economic implications of hypoparathyroidism in 374 patients in the U.S. aged 18 years or older who were diagnosed with the disorder for at least six months. The mean age of respondents was 49 years and the meantime with hypoparathyroidism of 13 years. Eight-five percent of respondents were female and 78 percent suffered from post-surgical hypoparathyroidism.
PARADOX was approved by an institutional review board, led by researchers from the Mayo Clinic, and conducted in conjunction with the Hypoparathyroidism Association. Data were collected through a 30-minute, web-based instrument which was developed with input from clinical experts, the Hypoparathyroidism Association and patients. This instrument was primarily disseminated via email to Hypoparathyroidism Association members.
PTH plays a central role in a variety of critical physiological functions, including closely modulating serum calcium and phosphate, regulating renal excretion of calcium and phosphate, activating vitamin D, and maintaining normal bone turnover. In patients with hypoparathyroidism, insufficient levels of PTH lead to low serum calcium, high serum phosphate, increased urinary calcium excretion, and decreased urinary phosphorus excretion. PTH deficiency can also disrupt skeletal homeostasis, leading to bone abnormalities. In addition, patients with insufficient levels of PTH are unable to convert native vitamin D into its active state to properly absorb dietary calcium.
NPS Pharma is a global biopharmaceutical company pioneering and delivering therapies that transform the lives of patients with rare diseases. The company’s current therapeutic areas of focus are gastrointestinal disease and endocrine disorders. These include short bowel syndrome, a potentially fatal gastrointestinal disorder in which patients may have to rely on parenteral nutrition for their survival; Hypoparathyroidism, a complex endocrine disorder in which the parathyroid glands are either absent or damaged, and the body produces insufficient or no parathyroid hormone; and autosomal dominant hypocalcemia, an ultra-rare, genetic disorder of calcium homeostasis caused by mutations of the calcium-sensing receptor gene. NPS Pharma continues to seek in-licensing opportunities to develop new therapies for a broad range of rare diseases and complements its proprietary programs with a royalty-based portfolio of products and product candidates that includes agreements with Amgen, GlaxoSmithKline, Janssen Pharmaceuticals, and Kyowa Hakko Kirin. NPS Pharma has operations in the U.S., Canada, Europe, Latin America and Japan.