A One of a Kind Flagship Drug for Your Irritable Bowel

Kanak is a member of The Motley Fool Blog Network -- entries represent the personal opinion of the blogger and are not formally edited.

Ironwood Pharmaceuticals (NASDAQ: IRWD) develops drugs for the treatment of gastrointestinal diseases.

The company recently launched its flagship product Linzess in the U.S to treat irritable bowel syndrome (IBS). The product was developed and commercialized in collaboration with Forest Laboratories for North America. The same product is under various development stages to promote in different geographies including Europe and Asia.

IBS market

IBS is a gastrointestinal disorder caused due to contraction of the colon muscle. It is not a disease as such, but a group of symptoms that generally occur together, including abdominal pain or discomfort. This results in diarrhea and constipation due to unusual bowel movement. It is classified as four subtypes: IBS with constipation (IBS-C), IBS with diarrhea (IBS-D), mixed IBS (IBS-M) and unsubtyped IBS (IBS-U). It is estimated that one in five Americans, mostly women, suffer from IBS. The disorder, although painful and discomfiting, does not usually cause permanent damage.

Limited first-line therapies are available although Novartis’s Zelnorm was taken off the market due to its risky side effects. Though generic and Over The Counter (OTC) products or laxatives are available, they are not as effective, thus the IBS market holds immense business opportunities globally. Two FDA approved drugs, Amitiza and Lotronex, are currently available for the treatment of IBS with constipation (IBS-C) and chronic idiopathic constipation (CIC).

Ironwood’s Linzess

Linzess (linaclotide) is the first and only guanylate cyclase-C (GC-C) agonist approved by the FDA for IBS-C and CIC indications in adults. It is an oral medication available in the form of capsules which inhibit the GC-C enzyme responsible for acute diarrhea. According to IMS Health, more than 70,000 Linzess prescriptions had been written since its launch on December 17, 2012 and until March. As of date, that number has risen to 200,000. The same product is expected to launch as Constella in the U.K. and Germany by Q2, 2013. In Europe, Ironwood will sell its product through its partner Almirall S.A. At present the company is only focusing on IBS-C, which has the predominant market.

Market performance

Pipeline: Ironwood and Forest completed further studies (Phase IIIb) to evaluate Linzess' effect on abdominal symptoms in patients with CIC. The company is likely to defer reporting trial results to Q3, 2013. Furthermore, the company is looking for additional development opportunities with linaclotide, the active ingredient of Linzess, on gastrointestinal disease.The company does have two more products candidates, IW-9179 and IW-2143. IW-9179 is a Phase II candidate used for treatment of functional dyspepsia and IW-2143 is in Phase I for treatment of anxiety. Although these candidates are still a long way off from the market, they are addressing disorders which have very similar symptoms to IBS, a disorder their active ingredient linaclotide has already successfully addressed.

Strong alliances: Besides Forest Laboratories and Almirall, Ironwood has partnered with Astellas Pharma and Astrazeneca for development and commercialization of linaclotide in Japan and China respectively.

<table> <thead> <tr><th> <p><strong>Name</strong></p> </th><th> <p><strong>Geography</strong></p> </th><th> <p><strong>Partner</strong></p> </th><th> <p><strong>Status</strong></p> </th></tr> </thead> <tbody> <tr> <td> <p>Linzess</p> </td> <td> <p>North America</p> </td> <td> <p>Forest Laboratories</p> </td> <td> <p>Launched (December 2012)</p> </td> </tr> <tr> <td> <p>Constella</p> </td> <td> <p>Europe</p> </td> <td> <p>Almirall S.A.</p> </td> <td> <p>Launched in Q2, 2013</p> </td> </tr> <tr> <td> <p>Linaclotide</p> </td> <td> <p>China</p> </td> <td> <p>Astrazeneca</p> </td> <td> <p>Phase III trial expected by Q3, 2013</p> </td> </tr> <tr> <td> <p>Linaclotide</p> </td> <td> <p>Japan</p> </td> <td> <p>Astellas</p> </td> <td> <p>Phase II</p> </td> </tr> </tbody> </table>

Ironwood also has joint collaboration with Depomed, a NASDAQ-listed biotech, to use the Acuform gastric retentive drug delivery technology for linaclotide. The company also has strategic alliances with Bionomics Limited to develop and commercialize Bionomics' anti-anxiety candidate BNC210.

Financial highlight: In the second quarter of 2013, net sales of Linzess as reported by Forest were $28.8 million. Ironwood has approximately $301 million in cash and short-term investments and a debt financing of $175 million till January. During this quarter, the company used $80 million of net cash for its operations.


Very little is know about what causes IBS, making its drug discovery fraught with the risk of unplanned side effects. A sacrifice to this problem was Zelnorm from Novartis, which, despite having superior efficiency for IBS, is no longer used and has been withdrawn from the market due to increasing risk of heart attack and strokes. FDA now approves Zelnorm only through a special treatment program; it can only be prescribed depending on how critical the disease is.

Amitiza (lubiprostone) capsules from Sucampo Pharmaceuticals (NASDAQ: SCMP) are indicated for the treatment of CIC and IBS. In 2004, Takeda signed a licensing agreement with Sucampo to market Amitiza in the U.S. and Canada. Recently, the product was approved by the FDA to use for opioid induced constipation (OUC) in adults. Sucampo received $10 million as milestone from Takeda for first sale of Amitiza as OIC treatment. In Q1, 2013, the U.S. net sales of Amitiza were $64.9 million as reported by Takeda, up by 7%, compared to $60.7 million in the same period 2012. The growth was due to increase in both volume and price.

In addition, Lotronex (alosetron) from Prometheus Laboratories is approved for use in IBS with severe diarrhea especially for women. The product was initially developed by GlaxoSmithKline (NYSE: GSK), however, in 2007, Prometheus Laboratories has taken over exclusive rights to Lotronex in the U.S. As of March 31, 2013, 14,551 physicians are enrolled under prescription programs for Lotronex. From September 2010 to March 2013, total number of prescriptions written were 110, 824. That includes gynecologists, internal medicine and family practice. In the recent quarter ended in March 31, 2013, 1063 physicians represent 80% of all Lotronex prescriptions.


As per IMS Health, approximately 60% of new patients use Linzess who were previously treated with OTC laxatives; 26% patients are converted from other branded drugs and 14% are from other available treatment. With increasing prescription data, Linzess will boost the collaborative revenue for Ironwood. Linzess has already been prescribed by more than 50% of gastroenterologists and around 20% of primary care physicians. The company continues to expand its prescriber base by introducing Linzess to the physician community in the U.S. and providing unrestricted access with tier 2 reimbursement.

Ironwood and Forest are exploring opportunities to expand the usage of Lonzess in dyspepsia, OIC and non-constipation IBS. By statistics, 8 million people suffer from OIC and 35 million from dyspepsia in the U.S. alone. Additional clinical studies involving linaclotide will strengthen Linzess’s potential further. Overall, Ironwood has the opportunity to expand its therapeutic base either as single or a combination therapy to support its growth.

Dr. Kanak Kanti De has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy. Is this post wrong? Click here. Think you can do better? Join us and write your own!

blog comments powered by Disqus