“We are delighted to be collaborating with Genentech” said Simon Pimstone, President and CEO of Xenon. “Genentech is among the world’s leading biotech companies and an ideal strategic partner for Xenon as we share a common emphasis on using human genetics for drug development. Further, this collaboration allows Xenon to both deepen and broaden our pipeline of novel medicines in development.”

Xenon and Genentech will collaborate on the discovery of new therapeutic approaches for treating pain. Under the terms of the agreement, Genentech has an exclusive license to compounds and a non-exclusive license to diagnostics from Xenon for development and commercialization of products. Xenon will receive an undisclosed upfront payment, research funding and is eligible to receive research, development and commercialization milestone payments, totaling up to $646 million for multiple products and indications. In addition, Xenon will receive royalties on sales of products resulting from the collaboration.

Michael Hayden, CSO of Xenon added: “This new alliance, which represents our sixth partnership with a major pharmaceutical company to date, once again highlights the keen interest in Xenon’s unique genetics approach and in our translational R&D capabilities.”

About Xenon Pharmaceuticals Inc. (Xenon)
Xenon is a privately owned, clinical genetics-based drug discovery and development company engaged in developing small molecule therapies based on the genetic causes of select metabolic, neurological and cardiovascular diseases. For more information, visit the Company’s website at http://www.xenon-pharma.com.

For more information regarding this press release, contact:
Dr. Robin Sherrington, VP, Business & Corporate Development (604) 484-3363 ddunn@xenon-pharma.com

This release contains forward-looking statements that are not based on historical fact. These forward-looking statements involve risks, uncertainties and other factors that may cause the actual results, events or developments to be materially different from those expressed or implied by such forward-looking statements. Readers are cautioned not to place undue reliance on such forward-looking statements.

Treatment of Na_V1.7-mediated pain in inherited erythromelalgia using a novel sodium channel blocker.

Targeting voltage-gated sodium channels for treating neuropathic and inflammatory pain

Xenon is developing XEN402 as a topical treatment for a variety of painful disorders including PHN, as it specifically targets sodium channels such as Na_v1.7. Sodium channels are highly expressed in sensory nerve endings and can be up-regulated in chronic painful conditions. In this phase 2a crossover study, the first phase 2a study with this topical product, 56 patients were alternately treated for three weeks with XEN402 and placebo ointments. The proportion of patients reporting >30% and >50% (clinically meaningful) reductions in pain was significantly greater for XEN402 than for placebo (p=0.049 for >30% and p=0.008 for >50%). In this trial, XEN402 also showed favorable trends in other co-morbidities commonly associated with PHN, including improvements in sleep. Importantly, neither dizziness nor drowsiness was observed in the trial, potentially differentiating topical XEN402 from the currently available oral treatments for PHN.

“These positive data represent an important step forward in the development of topical XEN402 for the treatment of chronic pain,” said Xenon President & CEO, Dr. Simon Pimstone. “The medical need and the market potential for an effective and safe neuropathic pain treatment are considerable. Over $4 billion per year is spent on such treatments, and despite this, many patients remain in considerable pain. Our PHN data showed XEN402 provides clinically meaningful responses by inhibiting those sodium channels involved in pain locally. These beneficial analgesic effects are even more encouraging given how well the product was tolerated. We believe that these findings considerably enhance the market opportunity for this product.”

In Xenon’s two earlier pilot proof-of-concept studies dosing XEN402 orally, the compound was shown to provide relief from inflammatory dental pain and from the debilitating neuropathic pain associated with inherited erythromelalgia. Inherited erythromelalgia is caused by gain-of-function mutations in Na_v1.7 and the XEN402 findings support its capacity to inhibit Na_v1.7 mediated pain. These two earlier trials indicated that XEN402 can suppress both inflammatory and neuropathic pain, suggesting that topical XEN402 could have broad utilities for multiple painful conditions.

Dr. Paul Goldberg, Xenon’s VP, Clinical added, “This topical product may differentiate itself from other pain treatments in a number of ways. It has an excellent safety profile and the potential to treat both neuropathic and inflammatory pain, and as an ointment, XEN402 may be applied to any anatomical region including the face or flexures. The product could be used both as a monotherapy, and given its negligible systemic exposures, as a safe adjuvant therapy to oral products. We look forward to the ongoing development of this exciting novel product.”

About Xenon Pharmaceuticals Inc.
Xenon is a privately owned, clinical genetics-based drug discovery and development company engaged in developing therapies focusing on novel targets in the areas of pain, cardiometabolic disease and diseases of iron metabolism. Xenon has multiple products in phase 1 and 2 clinical development. For more information, visit the Company’s website at www.xenon-pharma.com.

For more information regarding this press release, contact:
Dr. Robin Sherrington, VP, Business & Corporate Development, (604) 484-3300, ddunn@xenon-pharma.com

This release contains forward-looking statements that are not based on historical fact. These forward-looking statements involve risks, uncertainties and other factors that may cause the actual results, events or developments to be materially different from those expressed or implied by such forward-looking statements. Readers are cautioned not to place undue reliance on such forward-looking statements.

The Wightman Award is another major honour for Dr. Hayden, having previously been awarded the Order of Canada and Order of British Columbia, the Canadian Institutes of Health Research’s Health Researcher of the Year Award, LifeSciences BC’s Genome BC Award for Scientific Excellence and the Prix Galien Canada.

“I am thrilled to receive this award,” said Dr. Hayden during the awards ceremony this morning in Toronto. “As a physician scientist, to whom chance has given unusual opportunities, I am deeply aware of the degree to which my own success today is built upon the work, cooperation and struggles of others.”

“This is a wonderful moment for Michael and the Xenon team is extremely proud of Michael’s profound achievements. His scientific and entrepreneurial talents and the commitment he has made to finding novel cures for difficult to treat diseases have made us a better company and Canada a better scientific community,” said Dr. Simon Pimstone, a co-founder and President and Chief Executive Officer at Xenon Pharmaceuticals Inc. in Vancouver, Canada.

The Gairdner Awards are a highly respected international prize. Ten of the last 24 Nobel Prizes in medicine or physiology have been awarded to past Gairdner recipients. Prior to Dr. Hayden winning the Wightman Award, the last British Columbian to receive a Gairdner Award was the late UBC Chemistry Prof. Michael Smith, who won the 1986 Gairdner Foundation International Award and went on to win the 1993 Nobel Prize for Chemistry.

“I have known Michael and seen him in action for approximately twenty years and can think of no one in Canada more deserving,” said Mr. Michael Tarnow, the Chairman of Xenon’s Board of Directors and a past President and CEO of Merck Frosst Canada. “Michael’s research is innovative, meaningful and far reaching and is touching lives and providing hope for patients and family members literally all over the world. Michael is a most deserving recipient.”

An author of more than 600 publications, Dr. Hayden is the most cited author on Huntington’s disease in the world. He is well known for having developed a predictive genetic test for Huntington’s disease, which was the first ever predictive test for any genetic disorder. With Xenon he has also identified genes associated with rare disorders such as Tangier disease, juvenile hemochromatosis and congenital insensitivity to pain. These discoveries are leading to novel approaches for treating common diseases such as cardiovascular disease, anemia and pain.

About Xenon Pharmaceuticals Inc.
Xenon is a privately owned, clinical genetics-based drug discovery and development company engaged in developing small molecule therapies focusing in the areas of pain, cardiometabolic disease, and diseases of iron metabolism. For more information, visit the Company’s website at www.xenon-pharma.com.
For more information regarding this press release, contact:
Dr. Simon Pimstone, President & CEO, (604) 484-3300, ddunn@xenon-pharma.com

This release contains forward-looking statements that are not based on historical fact. These forward-looking statements involve risks, uncertainties and other factors that may cause the actual results, events or developments to be materially different from those expressed or implied by such forward-looking statements. Readers are cautioned not to place undue reliance on such forward-looking statements.

Under the terms of the agreement, Isis will receive an undisclosed upfront payment in the form of a convertible promissory note from Xenon to discover and develop antisense drugs to the targets hemojuvelin and hepcidin. Upon the identification of a development candidate, Xenon has the option to exclusively license the development and worldwide commercialization rights for these antisense drugs from Isis. In addition to license and option fees, Isis will be eligible to receive development and commercial milestones and royalties on sales of drugs licensed to Xenon under the collaboration as well as a portion of sublicense revenue.

“We are excited to be working with Isis, a world leader in the discovery and development of RNA-targeted therapeutics,” said Simon Pimstone, President & Chief Executive Officer of Xenon. “Using our human genetics platform, we validated hemojuvelin and hepcidin as novel targets for the treatment of anemia of inflammation where inhibition of these targets in the liver is predicted to treat AI by promoting red blood cell production. As such they are ideally suited to antisense therapeutics.”

“Hemojuvelin and hepcidin are promising targets for the treatment of anemia of inflammation, which have been largely inaccessible using traditional drug discovery methods. We are pleased to be working with Xenon and excited to apply our technology to such interesting and clinically meaningful targets,” said B. Lynne Parshall, COO and CFO of Isis. “A key component of our business strategy is to exploit the broad applicability of our antisense technology platform in order to target a wide range of diseases. By working with partners like Xenon, who are highly innovative and dedicated to a therapeutic area, we are able to expand the breadth of our antisense drug pipeline while staying focused on our internal drug discovery and development activities.”

AI is the second most common form of anemia worldwide and is associated with a wide variety of conditions including infection, cancer and chronic inflammation. AI is caused by the disruption of normal levels of iron in the body leading to poor iron availability for red blood cell production. This restricted iron availability also hampers the current treatment option recombinant erythropoietin (epo) to promote red blood cell production. Antisense therapeutics targeting hemojuvelin and hepcidin should reverse iron disturbances observed in AI and facilitate new red blood cell production.

“A key aspect of erythropoietin’s adverse effects, particularly in the cancer setting, has been the use of higher doses in some patients,” said Paul Goldberg, Xenon’s VP of Clinical Development. “This resistance to erythropoietin action is highly related to the restricted iron availability observed in AI. Inhibition of hemojuvelin or hepcidin may alleviate the erythropoietin resistance and offer alternative treatment options,” he added.

About Xenon Pharmaceuticals Inc.
Xenon is a privately owned, clinical genetics-based drug discovery and development company engaged in developing small molecule therapies focusing in the areas of pain, cardiometabolic disease, and diseases of iron metabolism. Xenon has multiple products in phase 1 and 2 clinical development. For more information, visit the Company’s website at www.xenon-pharma.com.

About Isis Pharmaceuticals, Inc.
Isis is exploiting its expertise in RNA to discover and develop novel drugs for its product pipeline and for its partners. The Company has successfully commercialized the world’s first antisense drug and has 22 drugs in development. Isis’ drug development programs are focused on treating cardiovascular, metabolic, and severe neurodegenerative diseases and cancer. Isis’ partners are developing antisense drugs invented by Isis to treat a wide variety of diseases. Isis and Alnylam Pharmaceuticals are joint owners of Regulus Therapeutics Inc., a company focused on the discovery, development and commercialization of microRNA therapeutics. Isis also has made significant innovations beyond human therapeutics resulting in products that other companies, including Abbott, are commercializing. As an innovator in RNA-based drug discovery and development, Isis has designed and executed a patent strategy that has provided the Company with strong and extensive protection for Isis’ drugs as well as all aspects of antisense drug discovery, development and manufacturing. Additional information about Isis is available at www.isispharm.com.

Isis Pharmaceuticals’ Forward-looking Statement
This press release includes forward-looking statements regarding Isis’ collaboration with Xenon Pharmaceuticals and the discovery and development of Isis’ antisense drugs for the treatment of anemia of inflammation. Any statement describing Isis’ goals, expectations, financial or other projections, intentions or beliefs is a forward-looking statement and should be considered an at-risk statement. Such statements are subject to certain risks and uncertainties, particularly those inherent in the process of discovering, developing and commercializing drugs that are safe and effective for use as human therapeutics, and in the endeavor of building a business around such drugs. Isis’ forward-looking statements also involve assumptions that, if they never materialize or prove correct, could cause its results to differ materially from those expressed or implied by such forward-looking statements. Although Isis’ forward-looking statements reflect the good faith judgment of its management, these statements are based only on facts and factors currently known by Isis. As a result, you are cautioned not to rely on these forward-looking statements. These and other risks concerning Isis’ programs are described in additional detail in Isis’ annual report on Form 10-K for the year ended December 31, 2009 and its most recent quarterly report on Form 10-Q, which are on file with the SEC. Copies of these and other documents are available from the Company.

Isis Pharmaceuticals is a registered trademark of Isis Pharmaceuticals, Inc. Regulus Therapeutics is a trademark of Regulus Therapeutics Inc.

Xenon Pharmaceuticals’ Forward-looking Statement
This release contains forward-looking statements that are not based on historical fact. These forward-looking statements involve risks, uncertainties and other factors that may cause the actual results, events or developments to be materially different from those expressed or implied by such forward-looking statements. Readers are cautioned not to place undue reliance on such forward-looking statements.

XEN402 has been developed by Xenon as a topical ointment formulation and recently concluded a 21-day cumulative dose safety and tolerability phase 1 study in normal human volunteers. The product was well tolerated and achieved good drug concentrations in the skin. Topical XEN402 is being developed by Xenon for painful neuropathic disorders such as PHN and targets the sodium channel sub-type Nav1.7. This target is highly expressed in sensory nerve endings and its expression has been shown to be up-regulated in chronic painful conditions such as PHN.

“This is an important step forward in the development of topical XEN402,” said Xenon President & CEO, Dr. Simon Pimstone. “This is a truly unique product built on our genetic studies that showed Nav1.7 deficient humans are completely unable to feel pain. By treating pain locally at its source through Nav1.7 block, topical XEN402 could be a very effective and safe treatment option. Our pre-clinical data show excellent efficacy with topical XEN402 in multiple inflammatory and neuropathic pain models when compared to other topical agents and additive effects to existing oral pain treatments. We are excited by these findings as the product could eventually treat multiple chronic painful conditions. This progress signifies another example of Xenon transitioning its target discovery engine to human proof-of-concept trials.”

Xenon’s VP, Clinical Development, Dr. Paul Goldberg referred to topical XEN402 as a “potentially transformative therapy as leading agents have significant side effects and often leave many patients still in pain. As such there is a large unmet medical need for a novel analgesic that is both effective and safe. We see topical XEN402 being used both as a monotherapy and as an adjuvant agent as well,” he added.

Xenon expects to conclude the phase 2 trial in Q1, 2011 with top-line data available in Q2, 2011.

About Xenon
Xenon is a privately owned, clinical genetics-based drug discovery and development company engaged in developing small molecule therapies focusing in the areas of pain, cardiometabolic disease, and diseases of iron metabolism. Xenon has multiple products in phase 1 and 2 clinical development. For more information, visit the Company’s website at www.xenon-pharma.com.

For more information regarding this press release, contact:

Xenon Contact
Dr. Robin Sherrington
VP, Business & Corporate Development
Phone: (604) 484-3300
Email: ddunn@xenon-pharma.com

This release contains forward-looking statements that are not based on historical fact. These forward-looking statements involve risks, uncertainties and other factors that may cause the actual results, events or developments to be materially different from those expressed or implied by such forward-looking statements. Readers are cautioned not to place undue reliance on such forward-looking statements.

“We are delighted to welcome Tarek to the Xenon team,” commented Simon Pimstone, Xenon’s President and CEO. “Tarek is a world-class R&D executive whose experience in discovering products, a number of which are now on the market, will further enhance Xenon’s capabilities. Tarek has had the unique experience of holding senior leadership positions within both biotech and more traditional pharmaceutical companies. His successful careers at Biochem Pharma and Wyeth Pharmceuticals (now Pfizer) have armed Tarek with best-in-class drug discovery and development practice and we are confident that Tarek will make a major contribution to Xenon’s future innovative R&D efforts.”

Dr. Mansour has spent nearly 25 years in the life sciences industry with positions at Biochem Pharma, and Wyeth Pharmaceuticals (now Pfizer). His most recent position at Wyeth Research was as VP, Chemical Sciences Head over multiple research sites. Dr. Mansour received his PhD in Chemistry from the University of Missouri – Columbia.

About Xenon

Xenon is a privately owned, clinical genetics-based drug discovery and development company engaged in developing small molecule therapies focusing in the areas of pain, cardiometabolic disease, and diseases of iron metabolism. Xenon has multiple products in phase 1 and 2 clinical development. For more information, visit the Company’s website at www.xenon-pharma.com.

For more information regarding this press release, contact:

Xenon Contact

Dr. Simon Pimstone
President & CEO
Phone: (604) 484-3300
Email: ddunn@xenon-pharma.com
This release contains forward-looking statements that are not based on historical fact. These forward-looking statements involve risks, uncertainties and other factors that may cause the actual results, events or developments to be materially different from those expressed or implied by such forward-looking statements. Readers are cautioned not to place undue reliance on such forward-looking statements.

“Our goal with this collaboration is to advance an early-stage R&D program by leveraging the technical strengths and research capabilities established by CDRD and DDI,” said Simon Pimstone, President and CEO of Xenon.

“This is a great opportunity to demonstrate DDI’s ability to collaborate with the local lifesciences and biotech industry. We intend to assist Xenon in reaching its early stage research goals by offering a high level of R&D expertise, as well as adding value by expediting certain early stage research milestones in this Xenon program,” said Natalie Dakers, Chief Executive Officer for CDRD and DDI.

About CDRD and DDI

The Centre for Drug Research and Development (CDRD) guides and supports early-stage drug development from BC’s top academic and health research institutions to increase the successful commercialization of new therapeutics. CDRD provides drug development expertise and infrastructure to enable researchers throughout BC to develop promising drug candidates. CDRD’s commercial arm, Drug Development Inc (DDI), licenses technologies from affiliated institutions, advances projects by leveraging CDRD’s expertise and infrastructure, and establishes working collaborations with other biotech and lifesciences companies. For more information, visit CDRD’s website.

About Xenon

Xenon is a privately owned, clinical genetics-based drug discovery and development company engaged in developing small molecule therapies based on the genetic causes of select metabolic, neurological and cardiovascular diseases. For more information, visit the Company’s website.

For additional information, contact:

CDRD
Jodi Regts
Director, Communications
(604) 221-7750 x182
jregts@cdrd.ca

Xenon
Dr. Robin Sherrington
Senior Director, Strategic Alliances
(604) 484-3363
ddunn@xenon-pharma.com

This release contains forward-looking statements that are not based on historical fact. These forward-looking statements involve risks, uncertainties and other factors that may cause the actual results, events or developments to be materially different from those expressed or implied by such forward-looking statements. Readers are cautioned not to place undue reliance on such forward-looking statements.

“We are very excited to be collaborating with Merck to define new therapeutics in the area of cardiovascular diseases,” said Simon Pimstone, President and CEO of Xenon. “With this deal, Xenon is continuing its strategy of risk mitigation by select partnering, while retaining ownership of other programs.”

In collaboration with Merck, Xenon will perform validation studies using its clinical genetics platform, as well as drug discovery and select preclinical development of small molecule compounds for those targets selected by a joint steering committee.

Under the terms of the agreement, Merck has the option to exclusively license targets and compounds from Xenon for development and commercialization. In return, Xenon receives research funding and is eligible for option exercise fees, research, development and regulatory milestone payments of up to US$94.5 million for the first target and up to US$89.5 million for each subsequent target. In addition, Merck will pay Xenon undisclosed royalties on sales of products resulting from the collaboration. Xenon retains the right to develop and commercialize certain compounds for which Merck does not exercise its option.

Michael Hayden, CSO of Xenon added: “We recognize that Merck is a leading pharmaceutical company with significant presence in and commitment to the cardiovascular space and they are an ideal strategic partner for Xenon. This new alliance, which represents our fifth partnership with a major pharmaceutical company, once again highlights Xenon’s R&D capabilities and validates our drug discovery platform.”

About Xenon

Xenon is a privately owned, clinical genetics-based drug discovery and development company engaged in developing small molecule therapies based on the genetic causes of select metabolic, neurological and cardiovascular diseases. For more information, visit the Company’s website at www.xenon-pharma.com.

For more information regarding this press release, contact:

Xenon Contact

Dr. Robin Sherrington
Senior Director, Strategic Alliances
Phone: (604) 484-3363
Email: ddunn@xenon-pharma.com
This release contains forward-looking statements that are not based on historical fact. These forward-looking statements involve risks, uncertainties and other factors that may cause the actual results, events or developments to be materially different from those expressed or implied by such forward-looking statements. Readers are cautioned not to place undue reliance on such forward-looking statements.

“We are delighted to have received this prestigious award, one of BIOTECanada’s four Gold Leaf Awards presented this year,” commented Simon Pimstone, Xenon’s President and CEO. “This honor is important and made even more so by the fact that it represents recognition by our industry peers of both our achievements to date and the potential that Xenon offers.”

“Xenon has made substantial progress in advancing its pipeline of novel compounds acting against targets derived from our clinical genetics approach. In the next 12 months we should have multiple products in clinical development for potential blockbuster markets. Our product pipeline is diverse, and we are excited to be advancing our discoveries into clinical opportunities,” Pimstone added.

About Xenon

Xenon is a privately owned, clinical genetics-based drug discovery and development company engaged in developing small molecule therapies focusing in pain, lipid modification for treating diabetes/obesity, and other diseases, as well as therapies for treating anemia and diseases of iron overload. Xenon has partnerships with Novartis Pharma AG, Roche and Takeda Pharmaceutical Company Ltd. For more information, visit the Company’s website at www.xenon-pharma.com.

For more information regarding this press release, contact:

Xenon Contact

Dr. Simon Pimstone
President & CEO
Phone: (604) 484-3300
Email: ddunn@xenon-pharma.com
This release contains forward-looking statements that are not based on historical fact. These forward-looking statements involve risks, uncertainties and other factors that may cause the actual results, events or developments to be materially different from those expressed or implied by such forward-looking statements. Readers are cautioned not to place undue reliance on such forward-looking statements.