Santarus Receives Previously Announced $20 Million Milestone for FDA Approval of ZEGERID OTC

Santarus, Inc. (NASDAQ:SNTS), a specialty biopharmaceutical company, today announced that it has received the $20 million milestone payment previously announced on December 1, 2009 relating to the approval of ZEGERID OTC^™ (omeprazole 20 mg/sodium bicarbonate 1100 mg capsules) under its over-the-counter (OTC) licensing agreement with Schering-Plough HealthCare Products, Inc., the consumer healthcare division of Merck & Co., Inc. Schering-Plough and Merck merged on November 3, 2009.

The U.S. Food and Drug Administration (FDA) approved Schering-Plough HealthCare Products’ New Drug Application (NDA) for ZEGERID OTC for OTC treatment of frequent heartburn on December 1, 2009. The OTC heartburn market in the U.S. is estimated at $1.7 billion based on data from Information Resources, Inc., a market research firm, and company estimates. ZEGERID OTC capsules are expected to be available on retail store shelves in the first half of 2010.

The NDA was submitted by Schering-Plough HealthCare Products under the terms of a license agreement for OTC proton pump inhibitor (PPI) products using Santarus’ proprietary technology. Santarus may be entitled to receive up to an additional $37.5 million in sales milestones. Santarus will also be entitled to a low double-digit royalty, subject to adjustment in certain circumstances, on net sales of any ZEGERID OTC products sold by Schering-Plough HealthCare Products under the license agreement. In turn, Santarus will be obligated to pay royalties to the University of Missouri on net sales of any such OTC products.

Santarus is continuing to manufacture, promote and sell its ZEGERID (omeprazole/sodium bicarbonate) prescription products in both 20 mg and 40 mg dosage strengths of omeprazole in the U.S. prescription market for PPI products. Approximately 96% of ZEGERID Capsules prescriptions are written for the 40 mg dosage strength. Prescription strength ZEGERID is indicated for the treatment of heartburn and other symptoms associated with gastroesophageal reflux disease (GERD), for the short-term treatment of erosive esophagitis diagnosed by endoscopy, for maintenance of healing of erosive esophagitis (controlled studies do not extend beyond 12 months), and for short-term treatment of active benign gastric ulcers and active duodenal ulcers.

Important Safety Information about Prescription Strength ZEGERID Capsules and Powder for Oral Suspension

The most frequently reported adverse events with ZEGERID are headache, diarrhea, and abdominal pain. In 178 critically ill patients treated with ZEGERID Powder for Oral Suspension, adverse events generally reflected the serious, underlying medical condition of the patients, but some adverse events occurred with more frequency in patients treated with ZEGERID Powder for Oral Suspension than in those treated with the comparator (acid-controlling) drug. For more information about these and other events, please see Table 13 of the full Prescribing Information at www.Zegerid.com. Symptomatic response to therapy does not preclude the presence of gastric malignancy. Atrophic gastritis has been noted occasionally in gastric corpus biopsies from patients treated long term with omeprazole.

ZEGERID Capsules contain 304 mg of sodium per dose. ZEGERID Powder for Oral Suspension contains 460 mg of sodium per dose. This should be taken into consideration for patients on a sodium-restricted diet.

Sodium bicarbonate is contraindicated in patients with metabolic alkalosis and hypocalcemia. ZEGERID is contraindicated in patients with known hypersensitivity to any component of the formulation.

Since both 20 mg and 40 mg ZEGERID contain the same amount of sodium bicarbonate (1100 mg in capsules, 1680 mg in packets of powder for oral suspension), two 20 mg capsules are not equivalent to, and should not be substituted for, one 40 mg capsule, and two 20 mg packets are not equivalent to, and should not be substituted for, one 40 mg packet.

About Santarus

Santarus, Inc. is a specialty biopharmaceutical company focused on acquiring, developing and commercializing proprietary products that address the needs of patients treated by gastroenterologists and other physicians. The company’s current commercial efforts are focused on ZEGERID^® (omeprazole/sodium bicarbonate), which is indicated for the treatment of certain upper GI diseases and disorders, and on GLUMETZA^® (metformin hydrochloride extended release tablets), which is indicated as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes. Santarus is also developing two late-stage lower GI product candidates, budesonide MMX^® and rifamycin SV MMX^®, for the U.S. market. Budesonide MMX is being investigated in two multicenter Phase III clinical trials for the induction of remission of mild or moderate active ulcerative colitis. Rifamycin SV MMX has been investigated in a Phase II clinical program in travelers’ diarrhea. More information about Santarus is available on the company’s Web site at www.santarus.com.

Santarus cautions you that statements included in this press release that are not a description of historical facts are forward-looking statements. These forward-looking statements include statements regarding anticipated launch timing for ZEGERID OTC. The inclusion of forward-looking statements should not be regarded as a representation by Santarus that any of its plans or objectives will be achieved. Actual results may differ materially from those set forth in this release due to the risks and uncertainties inherent in Santarus’ business, including, without limitation: the timing for launch of ZEGERID OTC; whether Schering-Plough is able to generate market demand and acceptance for ZEGERID OTC and, in turn, generate sales milestones and royalty payments for Santarus; Schering-Plough’s level of commitment, the potential for termination of the licensing arrangement and other risks related to the licensing arrangement; the scope and validity of patent protection for ZEGERID products, including the timing and outcome of the patent infringement lawsuit against Par Pharmaceutical, Inc., and Santarus’ and its strategic partners’ ability to commercialize products without infringing the patent rights of others; other difficulties or delays in development, testing, manufacturing and marketing of, and obtaining and maintaining regulatory approvals for, Santarus’ products; and other risks detailed in Santarus’ prior press releases as well as in public periodic filings with the Securities and Exchange Commission.

You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. All forward-looking statements are qualified in their entirety by this cautionary statement and Santarus undertakes no obligation to revise or update this news release to reflect events or circumstances after the date hereof. This caution is made under the safe harbor provisions of Section 21E of the Private Securities Litigation Reform Act of 1995.

Santarus^®, ZEGERID^® and ZEGERID OTC^™ are trademarks of Santarus, Inc. GLUMETZA^® is a registered trademark of Biovail Laboratories International S.r.l. licensed exclusively in the United States to Depomed, Inc. MMX^® is a registered trademark of Cosmo Technologies Limited.