Raptor Pharmaceuticals Doses First Patient in Phase 2b Clinical Trial of DR Cysteamine for Cystinosis

NOVATO, California — The Phase 2b clinical trial will enroll up to six cystinosis patientswith a history of good compliance using the currently availableimmediate-release form of cysteamine bitartrate, the only drug cleared formarketing by the U.S. Food and Drug Administration (“FDA”) and EuropeanMedicines Agency (“EMEA”) to treat cystinosis.

The clinical trial willevaluate safety, tolerability, pharmacokinetics and pharmacodynamics of asingle dose of DR Cysteamine in patients. Data from the study are expected inthe third quarter of 2009. Raptor plans to follow the Phase 2b clinical studywith a pivotal, Phase 3 clinical study in cystinosis patients anticipated tocommence in the fourth quarter of 2009.

DR Cysteamine is Raptor’s proprietary enteric-coated micro-beadformulation of cysteamine bitartrate contained in a gelatin capsule anddesigned for increased absorption, less frequent dosing and improvedtolerability relative to the current standard of care. Published studies haveshown that fewer than 25% of patients taking immediate-release cysteaminebitartrate are fully-compliant due to the drug’s strict every-six hour dosingschedule and dose-limiting side effects, including gastrointestinal (“GI”)problems such as stomach aches, nausea and vomiting.

Patrice Rioux, M.D., Ph.D., Raptor’s Chief Medical Officer stated, “Weare pleased that enrollment is now underway in our Phase 2b clinical trial incystinosis. This is an underserved patient population and there is acompelling need for an improved treatment option. Many patients are unable totake adequate levels of the drug to halt the progression of their disease,which gradually destroys the organs in the body. We believe DR Cysteaminecould have positive effects on the long-term health of cystinosis patients aswell as the quality of life for patients, their families and caregivers.”

Bruce Barshop, M.D., Ph.D., Professor of Clinical Pediatrics at UCSD andprincipal investigator for the cystinosis clinical trial, commented, “Theinitiation of this cystinosis trial offers us an opportunity to evaluate thepotential for an improved treatment invented here at UCSD and furtherdeveloped by Raptor. We’re pleased to collaborate with Raptor in this effortto advance the standard of care in cystinosis.”

About DR Cysteamine

DR Cysteamine is an enteric-coated micro-bead formulation of cysteaminebitartrate. Raptor obtained an exclusive, worldwide license to DR Cysteamine,as well as orphan drug designation from the FDA for DR Cysteamine for thetreatment of nephropathic cystinosis, through its December 2007 acquisitionof Encode Pharmaceuticals. In March 2008, Raptor acquired an exclusiveworldwide license to intellectual property from the University of California,San Diego for use of cysteamine and DR Cysteamine for the treatment ofnon-alcoholic steatohepatitis (“NASH”), a progressive liver disease believedto affect 2-5% of the U.S. population. In October, 2008 Raptor announced theinitiation of a Phase 2a clinical study of cysteamine bitartrate in NASHpatients, in collaboration with UCSD. In November, 2008 Raptor announced acollaboration with Centre Hospitalier Universitaire d’Angers, in France, tostudy DR Cysteamine in Huntington’s Disease, a rare, genetic neurologicaldisease.

About Raptor Pharmaceuticals Corp.

Raptor Pharmaceuticals Corp. (“Raptor”) is dedicated to speeding thedelivery of new treatment options to patients by working to improve existingtherapeutics through the application of highly specialized drug targetingplatforms and formulation expertise. Raptor focuses on underserved patientpopulations where it can have the greatest potential impact. Raptor currentlyhas product candidates in clinical development to treat nephropathiccystinosis, non-alcoholic steatohepatitis (“NASH”), Huntington’s Disease(“HD”), and aldehyde dehydrogenase (“ALDH2”) deficiency.

Raptor’s preclinical programs are based upon bioengineered novel drugcandidates and drug-targeting platforms derived from the humanreceptor-associated protein (“RAP”) and related proteins that are designed totarget cancer, neurodegenerative disorders and infectious diseases.

For additional information, please visit www.raptorpharma.com.


This document contains forward-looking statements as that term is definedin the Private Securities Litigation Reform Act of 1995. These statementsrelate to future events or our future results of operation or futurefinancial performance, including, but not limited to the followingstatements: that Raptor will be able to fully enroll and complete theclinical trial in cystinosis patients; that data will be available in thethird quarter of 2009; that Raptor will start a Phase 3 clinical trial incystinosis patients in the fourth quarter of 2009, if at all; that DRCysteamine will increase absorption, require less frequent dosing or improvetolerability relative to the current standard of care; that DR Cysteaminewill have a positive effect on cystinosis patients and increase their qualityof life; and that any of the Company’s clinical and preclinical drugcandidates will result in approved therapeutics. These statements are onlypredictions and involve known and unknown risks, uncertainties and otherfactors, which may cause the Company’s actual results to be materiallydifferent from these forward-looking statements. Factors which maysignificantly change or prevent the Company’s forward looking statements fromfruition include: that Raptor may be unsuccessful at raising funds tocontinue its development programs; Raptor may be unsuccessful in developingany products or acquiring products; that Raptor’s technology may not bevalidated as it progresses further and its methods may not be accepted by thescientific community; that Raptor is unable to retain or attract keyemployees whose knowledge is essential to the development of its products;that unforeseen scientific difficulties develop with the Company’s process;that Raptor’s patents are not sufficient to protect essential aspects of itstechnology; that competitors may invent better technology; and that Raptor’sproducts may not work as well as hoped or worse, that the Company’s productsmay harm recipients. As well, Raptor’s products may never develop into usefulproducts and even if they do, they may not be approved for sale to thepublic. Raptor cautions readers not to place undue reliance on any suchforward-looking statements, which speak only as of the date they were made.

Certain of these risks, uncertainties, and other factors are described ingreater detail in the Company’s filings from time to time with the Securitiesand Exchange Commission (the “SEC”), which Raptor strongly urges you to readand consider, including its Registration Statement on Form S-1, as amended,that was declared effective on August 7, 2008; its annual report on Form 10-Kfiled with the SEC on October 30, 2008, as amended by that Form 10-K/A filedwith the SEC on December 23, 2008; and its Form 10-Q filed with the SEC onApril 13, 2009, all of which are available free of charge on the SEC’s website at http://www.sec.gov. Subsequent written and oral forward-lookingstatements attributable to Raptor or to persons acting on its behalf areexpressly qualified in their entirety by the cautionary statements set forthin the Company’s reports filed with the SEC. Raptor expressly disclaims anyintent or obligation to update any forward-looking statements.

For more information, please contact: Karl Cahill, Investor Relations +1-858-531-6100 [email protected] The Ruth Group Sara Ephraim Pellegrino (investors) / Janine McCargo (media) +1-646-536-7002 / +1-646-536-7033 [email protected] / [email protected]

Karl Cahill, Investor Relations, +1-858-531-6100, [email protected]; or Sara Ephraim Pellegrino (investors), +1-646-536-7002, [email protected], or Janine McCargo (media), +1-646-536-7033