Why Good Drugs Sometimes Fail: The Bexxar Story

Xconomy National — 

Quite a few biotech entrepreneurs go to work each day operating under the assumption that clinical trial data is king. If you put together a rock-solid dataset from a big clinical trial that says your experimental drug beats today’s standard of care, then you’re onto something big, or so the line of thinking goes.

Everything should fall into place. Patients will demand the drug. Doctors will prescribe it. Your stock will soar. You’ll make a fortune.

Wrong. Sometimes great drugs reach the market, and flop. That sad story played out over the past decade with a drug from GlaxoSmithKline for non-Hodgkin’s lymphoma. It could have helped tens of thousands of patients, but never came close to fulfilling its potential.

The drug was tositumomab combined with iodine 131 (Bexxar). GlaxoSmithKline said recently that it will quit making and selling the drug in February 2014, a little more than a decade after it was approved by the FDA. Usage peaked in 2006, but sales have been dropping 30 percent annually since then. Fewer than 75 patients in the U.S. got the drug last year, a Glaxo spokeswoman recently told Oncology Times.

“It’s a shame to see this being pulled off the market,” said Anas Younes, the chair of the lymphoma service at Memorial Sloan-Kettering Cancer Center in New York, when we spoke by phone last week. “If you look at this drug, it has about a 70 percent response rate, in one shot. You don’t have to keep giving it for 2-3 years. It’s simple, with not much toxicity. Many patients could have benefitted.”

Anas Younes, chief of lymphoma service at Memorial Sloan-Kettering Cancer Center

Anas Younes, chief of lymphoma service at Memorial Sloan-Kettering Cancer Center

There are many reasons why Bexxar failed, which I’ll get to in a minute. But the story starts, like so many in biotech, with a tantalizing scientific concept.

The idea, driven by Mark Kaminski, Richard Wahl and colleagues at the University of Michigan in the 1980s, was simple. It was to take a genetically engineered antibody, aim it at a specific marker found in abundance on cancer cells, and tack on a dose of radiation to give it extra tumor-killing punch. This was the kind of product that molecular biologists had dreamed of since the late ‘70s, when there was talk of “magic bullets” or “targeted missiles” against cancer. Bexxar and its competitor—ibritumomab loaded with a radioactive isotope called yttrium-90 (Zevalin)—arrived on the U.S. market in the early 2000s as the pioneers of this new class of treatment known as “radioimmunotherapies.”

Bexxar, developed in the late ‘90s by South San Francisco-based Coulter Pharmaceutical and acquired in 2000 by Seattle-based Corixa, had a lot going for it. The drug was aimed at a protein marker called CD20, which was already a validated molecular target for cancer, based on the success a couple years earlier of a so-called “naked” antibody from Genentech and Idec Pharmaceuticals, rituximab (Rituxan). Corixa had a well-respected CEO in Steve Gillis who attracted scientific talent, and raised lots of cash. It had a Big Pharma partner in Glaxo to help it manufacture and market the drug to the fullest.

Most importantly, Bexxar had clinical trial data on its side. The pivotal study of Bexxar was small, but offered strong evidence. It enrolled 40 patients with non-Hodgkin’s lymphoma who had no other options left at the time, because their disease had worsened after they got rituximab and several rounds of chemotherapy. The trial showed that 63 percent of those very ill patients had significant tumor shrinkage on Bexxar, and the benefit lasted a median time of more than two years (25 months). About 29 percent of patients went into complete remissions, and researchers weren’t sure exactly how long they’d last because so many remissions were still ongoing at the time of FDA approval. Several patients from the earliest clinical trials in the early ‘90s were still alive more than a decade later, and became forceful advocates for the drug.

Like all cancer drugs, Bexxar came with some baggage—significant depletion of infection-fighting white blood cells, oxygen-carrying red blood cells, and clot-forming platelet cells. But those tended to be manageable side effects. There were warnings that the drug might cause nasty immune reactions sometimes associated with antibody infusions, but that’s also true for rituximab. It wasn’t a show-stopper for Bexxar.

Still, the drug was held up by a series of FDA questions and requests for information. The new drug application was first filed in June 1999, and wasn’t approved by the FDA until four years later. That delay, an excruciating time for Corixa, allowed a combo of Rituxan and chemotherapy more time to cement its position as the standard of care in non-Hodgkin’s lymphoma.

Despite the delays, it looked like … Next Page »

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16 responses to “Why Good Drugs Sometimes Fail: The Bexxar Story”

  1. JSchaible says:

    Nice article, Luke.

    The rad onc referral issue did play some role in the slow uptake, as well as its
    ultimate demise when it was shown to be no better than rituximab.

    But another issue you did not mention also lead to it being less favored.
    Given radiation exposure, patients were instructed to sleep alone for 1 to 2
    weeks after a dose, and to limit close contact (within 6 feet) to no more than
    6 hrs per day. Might not sound like a big issue, but for many with spouse
    or children, this is the kind of quality of life issue that made rituximab and
    newer agents to be the first line choice.

    • JSchaible–thanks. I heard about the need for patients to sleep alone, and keep their distance, but didn’t think it was that long.

      • Jamie Reno says:

        It’s a non-issue, Luke. Being in separate rooms for a couple weeks is nothing compared to the horrors of chemo, which last months and months. Are you lidding me? That is just another myth perpetrated by too many people. Bexxar is a breeze compared to chemo and Rituxan, and yes, no other treatment gives remissions even close to as long. I profile many lymphoma survivors in my book Hope Begins in the Dark http://www.hopebeginsinthedark.com, and I have interviewed literally thousands of lymphoma survivors over the past decade. Chemo and/or Rituxan aren’t even close to Bexxar (and Zevalin) as far as long remissions.

    • Sandy Montgomery says:

      To be given back my quality of life for over 16 years, my choice was a no brainer. I have been given the gift of sharing my life with my husband and watching my daughters (then 8 and 10 years old) grow into beautiful adults. They actually started a charity, have raised nearly $400,000 and are still going going strong in the fight to live after being diagnosed with an incurable cancer.

  2. Jamie Reno says:

    Nice story, Luke. The reader below is completely misguided if he thinks Bexxar has “quality of life” issues. Bexxar is a walk in the park compared to chemotherapy. A couple weeks in a separate bedroom? I’ll take that any day over the horrible nausea, vomiting, etc, that chemo brings. I am alive today because of Bexxar. When i was first diagnosed with stage 4 non-Hodgkin’s lymphoma, I did chemo, which gave me less than two years remission and made me very sick. Then I did Bexxar, which did not make me sick at all and has given me 14 years remission. Easy math!! I am a 20-year correspondent with Newsweek and a patient advocate and I’ve written extensively about Bexxar and its direct radio-immunotherapy competitor, Zevalin. I was the first journalist to break the story of GSK’s indefensible decision to kill Bexxar http://therenodispatch.blogspot.com/2013/08/breaking-exclusive-lifesaving-cancer.html . Your story covers most of the bases, but the comments from Younes at Memorial Sloan-Kettering are absurd. Younes says that the story about oncologists rejecting Bexxar because they don’t want to refer to outside medical centers is “exaggerated.” That is complete nonsense. It sadly happens all the time. Very few oncologists embraced Bexxar or told their patients that it was a viable option, and it has nothing to do with how well the drug works. GlaxoSmithKline and oncologists across the nation are equally to blame for the sad demise of this amazing drug, which gives longer remissions and has fewer side effects than the “standard” of care (chemo and/or Rituxan). I’ll continue supporting Bexxar, and I hope that public pressure can sway GSK to change its mind. Though that is unlikely. The truth is GSK gave up on this drug a long time ago, and never put enough of its vast resources behind this treatment. It is outrageous and sad that this drug, which is the very best option for the most common type of lymphoma, will soon be gone.

    • Carolyn Calderon says:

      Jamie, MOST people do NOT UNDERSTAND the type of Non Hodgkins Lymphoma WE HAVE, there are many different cell types. I describe our cancer as the dandelion that you never quite get at the root, although it is treatable it is NOT CURABLE!!! Thus this cancer will constantly reoccur, therefore drugs like BEXXAR are a GOD SEND to us, to do 2 treatments that are TARGETED TO HIT ONLY OUR CANCER CELLS, and have a remission for more than 10 plus years!!! The removal of Bexxar is a crushing blow to the millions of NHL patients!!!

  3. It’s interesting that GSK feels that the best strategy is now to drop Bexxar. Given the cost of developing new drugs one would have thought it would have tried innovative new approaches to the available markets around the world for Bexxar.

  4. Ross Bonander says:

    Thank you for researching and writing this. It reminds me of the problems companies are having bringing a therapeutic lymphoma vaccine to market, even if only in the consolidation or maintenance setting. I can’t imagine any patient choosing Rituxan over a proven therapeutic vaccine following induction therapy; a 5 second shot over a two hour infusion, retaining immune protection over remaining immunocompromised, etc.

  5. HammundS says:

    Nice article. This drug was a clusterf**k. You gotta work with the docs and manufacturing problems need to be worked out before marketing. Good science does not always win out. You have to back it up with a good business plan too.

  6. Name says:

    Lack of advertisement. If people who are sick with NHL (non-Hodgkin lymphomas) know about this drug and how good it is. They themselves would demand for it.

  7. IRISB says:


  8. Sue says:

    This Bexxar tragedy seems to tell patients that they are not receiving the most effective treatments but the ones their insurance will cover. What a tragedy, I was in the Bexxar study and have been in remission for another 12 years having been identified in 1985 with MOpp therapy previously. This is a huge mistake and the drug was proven highly effective!

  9. Guest says:

    I am shocked by this, yes, very tragic news.

  10. Sandy Montgomery says:

    I am shocked by this terribly distressing news. I, too, participated in a clinical trial for what is now called Bexxar at Stanford University in October, 1997 through March, 1998. My doctor in Louisville, KY was thrilled when I was pronounced a CCR–a complete clinical response from a cancer that is “incurable” 3 months later. Big deal I lost a bit of my immune system to live!
    I am well taken care of for that. Now, over 16 years later, I am alive and well and so happy!
    I had, sadly, watched so many go through the horrors of CHOPP, and other toxic regimens of chemotherapy, followed by bone marrow transplants that are not cures, and often deadly. It was time for me to begin CHOPP as the NHL was growing in typical fashion when we found out about this “wonder drug” being administered at Stanford in trials. I was elated to be accepted in their clinical trial. I was randomly selected for the “cold” study first, and when there were signs of relapse a couple of months later, I was able to roll over into the “hot” study. It’s hot all right! It saved my precious life!!
    How very sad for NHL patients everywhere.
    I would do anything to help Bexxar to be reinstated.
    This drug saves lives. Unbelievable, GSK.

  11. Emil says:

    What happened to the oath or creed that doctors are bound by to preserve life and / or the quality of life. It seems like it gets trumped by greed of money as in not referring patients beyond their scope of treatment!!!

  12. Suzie says:

    I work in a large cancer center in the south east and have been involved in the administration of both Zevalin and Bexxar. I actually did a presentation on the 5 year success rate of our patients receiving these drugs. Yes, it could be a hassle with the drug coming from a different country …as mentioned snow storms and different holidays and factories being closed for maintenance…but the drugs worked though some of our patient were on lifetime blood or platelet transfusions. As the manager of the infusion center I was also well aware of the reimbursement issues …private practices always referred their patients to our hospital based center…we survived and more importantly our patients were survivng. I am sorry about this decision.