Cytochroma announces positive Phase 1/2 results for CTAP101 capsules in
non-dialysis chronic kidney disease patients

MARKHAM, ON, May 25 /CNW/ - Cytochroma today announced positive Phase 1/2 results for CTAP101 Capsules, a product being developed to treat secondary hyperparathyroidism (SHPT) associated with vitamin D insufficiency in non-dialysis chronic kidney disease (CKD) patients. The study demonstrated that a single dose of CTAP101 Capsules was safe, effective and well tolerated. The study also demonstrated that the mechanism to lower intact parathyroid hormone (iPTH) levels in CKD patients with vitamin D insufficiency is more complex than simply boosting blood vitamin D levels.

"We have gained significant new insights into the treatment of secondary hyperparathyroidism associated with low blood vitamin D levels in patients with chronic kidney disease," stated Dr. Charles W. Bishop, Cytochroma's President and Chief Executive Officer. "We are pleased to see that a single dose of CTAP101 Capsules resulted in reliable improvement of vitamin D status with meaningful and sustained suppression of elevated intact PTH. Intravenous delivery of the same active ingredient did not lower intact PTH despite restoration of blood vitamin D to adequate levels. The lack of effect of intravenous delivery is consistent with the recent body of evidence built up by Cytochroma's applied research team indicating that mega-doses of vitamin D, the current standard of care for SHPT associated with vitamin D insufficiency, is inefficient and only sporadically effective. Based on the results of this Phase 1/2 study, Cytochroma is looking to advance CTAP101 Capsules into a larger repeat-dose Phase 2 study in CKD patients as rapidly as possible."

The completed trial was a randomized, open-label, single-dose study to evaluate the pharmacokinetics, pharmacodynamics, safety and tolerability of two different oral doses of CTAP101 Capsules and an intravenous dose of the same active ingredient. Twenty-eight patients with stage 3 or 4 CKD were treated in the study having endpoints of blood vitamin D levels, adverse events, physical and clinical laboratory assessments, and changes in serum calcium, phosphorus and iPTH.

The results showed that a single dose of CTAP101 Capsules achieved normalization of mean blood vitamin D levels and a sustained, clinically important reduction in serum iPTH levels. A comparable reduction in iPTH levels was not observed in the group receiving intravenous therapy despite an immediate and greater increase in blood vitamin D levels. Mean serum calcium and phosphorus levels remained in the normal range in all three treatment groups throughout the study. There were no serious adverse events during the study.

About Chronic Kidney Disease (CKD)

CKD is a condition characterized by a progressive decline in the function of the kidney, which is normally responsible for excreting waste and excess water from the body, and for regulating various hormones. CKD is classified in five different stages - mild (stage 1) to severe (stage 5) disease - as measured by the kidney's glomerular filtration rate. According to the National Kidney Foundation, CKD afflicts over 26 million people in the United States (U.S.), including more than eight million patients with moderate (stages 3 and 4) and severe (stage 5) forms of CKD. In stage 5 CKD, kidney function is minimal to absent and patients require regular dialysis or a kidney transplant for survival.

About Vitamin D Insufficiency

Vitamin D insufficiency is a condition in which the body has low blood levels of vitamin D prohormones, collectively known as 25-hydroxyvitamin D. An estimated 70-90% of CKD patients have vitamin D insufficiency, which can lead to SHPT and resultant debilitating bone diseases. Mounting evidence continues to link vitamin D insufficiency with progression of CKD, cardiovascular morbidity, and increased mortality.

About Secondary Hyperparathyroidism (SHPT)

SHPT is a condition commonly associated with CKD in which the parathyroid glands secrete excessive amounts of parathyroid hormone (PTH). Excess PTH secretion arises as a result of either vitamin D insufficiency, or due to impaired kidneys that are unable to produce sufficient quantities of vitamin D hormones to maintain a state of balance (homeostasis) between calcium and phosphorus in the body. Prolonged elevation of PTH causes excessive calcium and phosphorus to be released from bone into the blood, leading to elevated serum calcium and phosphorus, softening of the bones (osteomalacia) and calcification of vascular tissues. SHPT affects 40-60% of patients with moderate CKD and approximately 90% of patients with severe CKD.

About CTAP101 Capsules

CTAP101 Capsules is being developed as a first-in-class treatment for secondary hyperparathyroidism associated with vitamin D insufficiency in CKD patients. The product is designed to gradually and reliably boost circulating vitamin D pro-hormone levels above the minimum adequate level established by the National Kidney Foundation in its Kidney Disease Outcomes Quality Initiative (K/DOQI) Guidelines, while also lowering the risk of vitamin D-related side effects. CTAP101 Capsules are intended to help nephrologists treat and/or prevent SHPT associated with vitamin D insufficiency.

About Cytochroma

Cytochroma is a clinical stage specialty pharmaceutical company focused on developing and commercializing proprietary products to treat and prevent the clinical consequences of vitamin D insufficiency and SHPT associated with CKD. The Company specializes in developing new vitamin D therapies which are designed to safely and effectively treat patients with stage 3, 4 or 5 CKD. Cytochroma has three product candidates in clinical development for CKD patients: CTA018 Injection and CTAP201 Injection are being developed for the treatment of SHPT in stage 5 CKD, while CTAP101 Capsules are being developed for the treatment of vitamin D insufficiency and associated SHPT in stage 3 and 4 CKD. CTA018 Injection is being developed in partnership with Mitsubishi Tanabe Pharma Corporation for the United States (U.S.) and Asian markets, and Cytochroma retains co-promotion rights for this product in the U.S. In addition, Cytochroma is developing novel therapies to treat hyperphosphatemia in CKD patients.

For more information about Cytochroma, please visit www.cytochroma.com.

For further information: Cytochroma Investors: Gordon Ngan, Executive Director, Corporate Development, Tel: [phone] ext. 333, [email protected]; Cytochroma Media: Robert Stanislaro (FD), Tel: [phone], [email protected]