Orphan Technologies Publishes Study Showing Prevalence of Classical Homocystinuria Substantially Higher Than Previously Published Estimates

Lexington, Mass.–(BUSINESS WIRE)–Orphan Technologies, a company dedicated to helping patients control their homocysteine levels, published study showing that 12,113 patients in the United States are diagnosed with classical homocystinuria (HCU) using strict ICD-10 diagnostic criteria in the U.S. This prevalence rate is substantially higher than previously published estimates but in-line with genetic modeling estimates.

– Rare metabolic disorder with no adequate treatment options affects an estimated 12,113 patients according to strict ICD-10 diagnostic claims data

– Healthcare costs for patients with ICD-10 diagnosed classical homocystinuria were similar to those for patients with phenylketonuria, indicating many of these diagnosed patients require additional therapeutic interventions

The study, published in the journal BMC Health Services Research, also demonstrated that healthcare costs associated with ICD-10 diagnosed HCU patients were similar to those associated with diagnosed phenylketonuria (PKU) – a rare metabolic genetic disease which affects approximately 15,000 people in the U.S. Overall, the data suggest HCU is often not diagnosed until later in life when homocysteine testing is often conducted, highlighting the need for earlier diagnosis and physician education. Orphan Technologies is developing OT-58, a novel, enzyme therapy designed to reduce plasma and tissue homocysteine levels. OT-58 is currently in a Ph1/2 clinical study in classical HCU patients.

“Our longstanding mission is to reduce the disease burden of HCU patients, who currently have limited treatment options,” commented J. Frank Glavin, CEO of Orphan Technologies. “We are confident that OT-58 could be a lifechanging new therapy for these patients. As is often the case with rare diseases, these data demonstrate that there are many more people affected by the disease than previously published estimates assume. While we are diligently working to provide a new treatment option that can reduce and control homocysteine levels, we recognize that our healthcare system also needs to do a better job of screening and identifying patients as early as possible. We look forward not only to seeing how OT-58 may be able to benefit HCU patients, but how we can partner with patient groups and the medical community to ensure patients are diagnosed as soon as possible to delay or prevent complications associated with this disease.”

The study, led by Orphan Technologies, compared characteristics, healthcare use and costs, and projected prevalence between patients with ICD-10 diagnosed HCU, patients with elevated total homocysteine (tHcy) and no ICD-10 diagnosis, as well as PKU patients. The team used U.S administrative claims data from the IBM® Marketscan® Research Databases to calculate the total prevalence of classical HCU by analyzing patients based on strictly defined diagnosis criteria, broadly defined diagnosis criteria, and elevated tHcy without an ICD-10 diagnosis. ICD-10 codes are used by doctors, health insurance companies, and public health agencies to represent diagnoses. Every disease has its own distinctive ICD-10 code. Prevalence, healthcare costs, frequencies of comorbidities and demographics associated with all groups were evaluated and compared to those associated with PKU.

Based on these data 12,113 patients are estimated to have ICD-10 diagnosed HCU using strict criteria and 31,162 to have HCU using broad diagnostic criteria. Additionally, ICD-10 diagnosed HCU patients had 3-4 times the rate of hospitalizations and more than twice as many total days of hospitalization than patients with PKU. As a result, inpatient costs contributed significantly more to overall healthcare costs among patients with diagnosed HCU compared to PKU patients.

About the Phase 1/2 Clinical Trial of OT-58 in Homocystinuria
The CBS-HCY-CT-01 study is a double-blind, randomized, placebo-controlled, phase 1/2 study to assess the safety, tolerability, pharmacokinetics, pharmacodynamics, and clinical effects of OT-58 in patients with cystathionine beta-synthase deficient homocystinuria. The primary endpoint of the Phase 1 portion of the study is safety. Secondary endpoints include evaluation of pharmacokinetic and pharmacodynamic parameters. More information on this OT-58 clinical study, including participation criteria, is available here.

About Homocystinuria
Classical homocystinuria is a rare genetic metabolic disorder caused by a deficiency in the enzyme cystathionine beta synthase (CBS). CBS is a pivotal enzyme in the conversion of the amino acid methionine to homocysteine and then to cysteine. Classical homocystinuria leads to significantly elevated levels of the amino acid homocysteine that can result in debilitating comorbidities in patients including severe cardiovascular, skeletal, neurologic and ophthalmologic complications. The current treatment for patients with classical homocystinuria is a severely protein restricted diet and compliance with these dietary restrictions is extremely difficult, regularly resulting in inadequate metabolic control and lack of disease control.

About OT-58
OT-58 is a modified recombinant enzyme therapy in development for patients suffering from the rare disease classical homocystinuria. OT-58 is designed to help patients reduce their homocysteine levels and restore a normal lifestyle.

About Orphan Technologies
Orphan Technologies is dedicated to developing novel therapies to dramatically improve the lives of patients suffering from the rare disorder, classical homocystinuria, and related diseases. OT-58, our lead drug development candidate, has been optimized as an enzyme therapy for classical homocystinuria, a genetic disease characterized by debilitating cardiovascular, skeletal, neurologic, and ophthalmologic complications. OT-58 is designed to reduce homocysteine levels via a targeted mechanism of action and may have therapeutic applications in other diseases. For more information, please visit


Orphan Technologies
J. Frank Glavin