-- MMD Phase 2 Trial Fully Enrolled -- RICHMOND, Va., July 21 /PRNewswire-FirstCall/ -- Insmed Inc. (Nasdaq CM: INSM), a developer of follow-on biologics (FOBs) and biopharmaceuticals, today provided an update on the status of its IPLEX(TM) development program. Insmed's Phase 2 trial of IPLEX(TM) in Myotonic Muscular Dystrophy (MMD), which was initiated in December 2007, has seen a strong patient and physician interest and is now fully enrolled. The trial is a six month, randomized, double-blind, placebo-controlled trial conducted at 13 research centers across the USA. The trial endpoints include the six-minute walk test, an FDA-accepted measure of endurance, and various conventional measures of muscle function, muscle strength, cognitive function, gastrointestinal function, general health, pain, insulin sensitivity, safety and tolerability As previously announced, a substantial portion of the external costs associated with the study are expected to be covered by an approximately $2.1 million grant awarded to Insmed by the Muscular Dystrophy Association in late 2007. IPLEX(TM) also continues to be used as part of an Expanded Access Program (EAP) in partnership with the Italian Ministry of Health for the treatment of Amyotrophic Lateral Sclerosis (ALS), or Lou Gehrig's disease. Additional subjects are being enrolled as the program progresses and IPLEX(TM) continues to demonstrate that it is safe and well tolerated in the subject population. To date the EAP has grown to include 22 physicians, and approximately 100 patients have been enrolled in the program. During the second quarter of 2008, cost recovery revenue from the EAP is expected to be approximately $2.6 million as compared to $1.2 million during the same period last year and $2.3 million in the first quarter of 2008. For the first half of 2008, Insmed expects the EAP to generate approximately $4.9 million in cost recovery revenue, compared to $1.9 million in the first half of 2007 and $5.4 million generated during the whole of 2007. About Myotonic Muscular Dystrophy Myotonic muscular dystrophy (MMD), also known as myotonic dystrophy, dystrophia myotonica or Steinert's disease, is the most common type of adult muscular dystrophy, affecting 1 in 8000 individuals (approximately 37,000 people in the United States). Myotonic dystrophy patients develop progressive muscle wasting and weakness in the hands, forearms, legs, neck and face, as well as cataracts and cardiac arrhythmias, and eventually can become totally disabled, dying usually from respiratory or cardiac failure. At present, there is no treatment to reverse most of these symptoms. For more information about myotonic muscular dystrophy, please visit http://www.mda.org/ . About Amyotrophic Lateral Sclerosis Amyotrophic Lateral Sclerosis (ALS), often referred to as Lou Gehrig's disease, is a progressive neurodegenerative disease that attacks nerve cells in the brain and spinal cord resulting in muscle weakness and atrophy. The life expectancy of an ALS patient averages about two to five years from the time of diagnosis. For more information about ALS visit http://www.alsa.org/ . About IPLEX(TM) IPLEX(TM) is a complex of recombinant human insulin-like growth factor-I (rhIGF-I) and its predominant binding protein IGFBP-3 (rhIGFBP-3). The drug, approved in the United States in December 2005 for the treatment of children with growth failure due to severe primary IGF-I deficiency, is currently being investigated in MMD and ALS. About Insmed Insmed Inc. is a biopharmaceutical company with unique protein process development and manufacturing experience and a proprietary protein platform aimed at niche markets with unmet medical needs. For more information, please visit http://www.insmed.com/ . Forward-Looking Statements This release contains forward-looking statements which are made pursuant to provisions of Section 21E of the Securities Exchange Act of 1934. Investors are cautioned that such statements in this release, including statements relating to planned clinical study design, regulatory and business strategies, plans and objectives of management and growth opportunities for existing or proposed products, constitute forward-looking statements which involve risks and uncertainties that could cause actual results to differ materially from those anticipated by the forward-looking statements. The risks and uncertainties include, without limitation, risks that product candidates may fail in the clinic or may not be successfully marketed or manufactured, we may lack financial resources to complete development of product candidates, the FDA may interpret the results of studies differently than us, the FDA may not establish specific guidelines for a pathway for the approval of FOB products, FOB products may not be accepted by consumers, competing products may be more successful, demand for new pharmaceutical products may decrease, the biopharmaceutical industry may experience negative market trends, our entrance into the follow on biologics market may be unsuccessful, our common stock could be delisted from the Nasdaq Capital Market and other risks and challenges detailed in our filings with the U.S. Securities and Exchange Commission, including our Annual Report on Form 10-K for the year ended December 31, 2007. Readers are cautioned not to place undue reliance on any forward-looking statements which speak only as of the date of this release. We undertake no obligation to publicly release the results of any revisions to these forward-looking statements that may be made to reflect events or circumstances that occur after the date of this release or to reflect the occurrence of unanticipated events. Investor Relations Contact: Brian Ritchie - FD 212-850-5683 Corporate Communications Contact: John Procter - Gibraltar Associates 202-879-5808 DATASOURCE: Insmed CONTACT: Investor Relations, Brian Ritchie, of FD, +1-212-850-5683, ; or Corporate Communications, John Procter, of Gibraltar Associates, +1-202-879-5808, , both for Insmed Web site: http://www.insmed.com/ http://www.mda.org/ http://www.alsa.org/

Copyright