"Pfizer Inc. https justapproved drug Xalkori the first new medicine in more than six years for deadly lung cancer https proves the value of precisely targeting rare diseases linked to gene variants cancer https specialists and Pfizer executives said Tuesday. The drug was approved Friday in the U.S. along with a companion diagnostic test for just a small subset of lung cancer patients. It epitomizes drugmakers new strategy of developing very expensive but effective medicines for relatively few patients to replace the blockbusters for the masses now getting competition from generic drugs.  Its also in the vanguard of longawaited personalized medicine in which doctors identify patients with gene changes or variations that fuel their disease and then try to match them with new medicines that specifically target those genes.  This is a paradigm shift Dr. Paul A. Bunn Jr. a University of Colorado professor and cancer researcher involved in testing Xalkori told journalists during a conference call hosted by Pfizer. It used to be that everybody with cancer was treated the same with surgery and chemotherapy.  Xalkori a pill with relatively minor side effects compared to the hair loss and nausea that chemotherapy can cause was approved for the roughly  percent of patients with advanced nonsmall cell lung cancer who have whats called the ALK fusion gene.  When ALK short for anaplastic lymphoma https kinase and another gene on the same chromosome rearrange their positions and fuse together the ALK gene stays on constantly fueling cancer cell growth. Xalkori works by blocking the kinase enzyme key to that process. About  Americans a year develop this cancer Pfizer said. Those patients called ALK positive now can be identified with a  molecular diagnostic test developed by Pfizers partner Abbott Molecular Oncology. The test was also approved Friday.  Youre going to be sparing individuals side effects and the waste of resources time and drug that really isnt going to help them Dr. Mark Kris head of the thoracic oncology service at Memorial SloanKettering Cancer Center https in New York said during the call. Normally doctors choose among different chemotherpay regimens for each patient and they may not pick an effective one.  In Pfizerfunded early and midstage studies that led to Xalkoris approval tumors disappeared shrank or stopped growing in just over half of patients for nearly two years on average. Research to determine overall survival is ongoing.  By comparison nonsmall cell lung cancer  about  percent of cancer cases  is tough to treat and kills nearly  percent of patients within five years. Lung cancer is the top killer among cancers worldwide.  Xalkori known chemically as crizotinib costs about  a month and is taken until it stops fighting tumors at which point patients likely would be put on older chemo drugs they hadnt taken yet. Pfizer has started a Xalkori patient assistance program with a maximum  monthly copayment for insured patients meeting certain financial limits. Insurers are expected to cover the drug for ALKpositive patients.  Jeff Wigbels an investment bank portflio manager treated in one of the drug studies said when he started taking it he couldnt eat because cancer had spread to his throat. Within a week he could eat again and soon scans of his lung and throat no longer showed tumors.  It was just an amazing experience he said.  Another patient Richard Heimler a former nonprofit executive said he had one cancerous lung removed seven years ago and repeatedly had new tumors surgically removed from his brain and the other lung along with chemotherapy. He began taking Xalkori  months ago and still takes a pill twice a day.  My tumors have either disappeared shrunk or are stable said Heimler and hes functioning well again.  Pfizer is currently running two latestage studies that compare Xalkori to different chemotherapy treatments that have been the standard of care. Its unusual to get approval before completing such large latestage studies. Xalkori was approved remarkably quickly just four years after Japanese researchers reported they had identified the ALK gene variation.  Pfizer is awaiting approval from regulators in the European Union https Switzerland Japan and Korea and also is testing crizotinib against other types of cancer. Pfizer said  percent to  percent of patients with nonsmall cell lung cancer have the ALK gene fusion. But one research group presented data at a recent cancer conference showing  percent of those patients have it.  Pfizer needs some big sellers because its . billionayear cholesterol fighter Lipitor the worlds topselling drug loses U.S. patent protection on Nov. . That starts an unprecedented wave of muchcheaper generic versions of many drugs taken daily by millions.  Geno Germano head of Pfizers specialty care and oncology business said Xalkoris development shows Pfizers core research operation has bounced back.  After successes including Lipitor antidepressant Zoloft and impotence pill Viagra in the s Pfizers inhouse scientists have had a string of highprofile drugs fail in patient testing in recent years. Thats forced the company to acquire many new drugs through acquisitions and licensing deals.    On the Web http"