Altus Pharmaceuticals Presents Positive Data from Phase I Study of ALTU-238; First Patients Dosed in Phase II Trial in Adults with Growth Hormone Deficiency.

CAMBRIDGE, Mass. -- Altus(R) Pharmaceuticals Inc., a company which is developing protein therapies to treat gastrointestinal and metabolic diseases, today announced results from a Phase I clinical trial for ALTU-238, a long-acting crystalline formulation of recombinant human growth hormone (somatropin). The data were presented at the 7th joint meeting of the European Society for Paediatric Endocrinology and the Lawson Wilkins Pediatric Endocrine Society (ESPE/LWPES) in Lyon, France on Saturday, September 24. ALTU-238 is a novel, subcutaneously administered once-per-week formulation of recombinant human growth hormone that employs Altus' proprietary protein crystallization and formulation technology.

In the Phase I clinical trial conducted in healthy adults, ALTU-238 produced a pharmacokinetic and pharmacodynamic profile consistent with once weekly dosing. The pharmacokinetic profile of ALTU-238 showed no burst release and a significantly extended time to reach maximum serum growth hormone concentration. Increases in serum IGF-1 levels with a single injection of ALTU-238 were comparable to those achieved in subjects receiving the same amount of growth hormone with 7 daily injections of Nutropin AQ. In addition, ALTU-238 was well tolerated and easily administered through a small 30 gauge needle.

"The positive data presented at ESPE/LWPES provide the basis for our recently initiated multi-center Phase II trial of ALTU-238 in adults with growth hormone deficiency," said Dr. Alan Kimura, Vice President of Clinical Development and Medical Affairs at Altus. "We believe that ALTU-238 may provide growth hormone-deficient patients with a once-weekly injection, while currently marketed products require daily injections. If ultimately approved, a long-acting treatment such as ALTU-238 could thereby improve the quality of life and convenience for these patients."

Sheldon Berkle, President and Chief Executive Officer of Altus Pharmaceuticals said, "We are excited about the start of the ALTU-238 Phase II trial based on the positive Phase I data. In this Phase II trial, we are seeking to demonstrate that our proprietary protein crystallization technology will enable extending the release of injectable protein therapeutics without encapsulating using polymers, or otherwise fundamentally changing the molecule."

About Growth Hormone Deficiency and Growth Failure

Growth hormone disorders occur when the production of growth hormone, secreted via the hypothalamic-pituitary axis (GHRH-GH-IGF1), is disrupted. Growth hormone plays a critical role in stimulating bone growth and development and it is involved in the production of muscle and in the breakdown of fats. In children, when there is a complete absence of growth hormone, severe growth retardation results. When there is a partial deficiency of growth hormone in children, short stature results. Recombinant human growth hormone (rhGH) products are currently approved to treat multiple growth disorders, including pediatric and adult growth hormone deficiency, Turner Syndrome, chronic renal insufficiency, idiopathic short stature, Prader-Willi Syndrome, short bowel syndrome and muscle wasting in patients with HIV.

About Altus Pharmaceuticals Inc.

Altus(R) Pharmaceuticals is focused on developing and commercializing novel protein therapies for patients with gastrointestinal and metabolic diseases. Altus is using its proprietary protein crystallization technology to develop orally-delivered and injectable protein therapies. Altus is committed to improving the quality of life of patients by meeting their unmet medical needs. More information about Altus and its clinical development programs can be found at www.altus.com.