Some background on Cometriq (Cabo) with regard to kidney cancer
Chris’s response to Cabo has generated a lot of interest in the drug. So, based on our research and experience, I thought I’d write a little about the drug – who should consider the drug and how folks can get access to it.
Cabozantinib (marketing name Cometriq, formerly known during clinical trials as XL-184) is an anti-angiogenic drug that inhibits the tyrosine kinases c-MET and VEGFR2. It’s similar to other TKIs, like Sutent or Votrient, but the addition of the c-MET inhibitor is what makes it novel.
Chris, Dena’s editor, here: Dena, no one knows what you just said. At least I don’t. This is a blog, not a medical journal. Stop trying to show off with fancy words like “kinases.” And “is.” Talk English. Or some corrupted version of it.
Chris, I think you’re underestimating our readers. Who amongst us doesn’t love a good kinase?
How would you like a good kick in the kinase?
Okay, okay, for you, I will simplify. Cabo is similar to other cancer drugs that are currently used for kidney cancer. These are oral drugs that help block blood vessel growth to tumors. Without the nutrients from the blood vessels, the tumors will stop growing – or even better die. Cabo is like these drugs, but it’s different because it uses a cellular pathway that other drugs don’t use.
Once a drug is approved by the FDA, it’s given a marketing name. So, even though we followed it in trial by its generic name – Cabozantinib, or Cabo for short – the official brand name is Cometriq. To give you another example: Tylenol is a marketing name, the generic name is Acetaminophen.
The developer and manufacturer of the drug is a San Francisco-based company called Exelixis. The drug is being tested in many cancers, including prostate, lung, ovarian, melanoma and breast. There’s a lot of excitement about it in the cancer community.
On November 30th, the drug was approved by the FDA for Medullary Thyroid cancer. The reason it was so quickly approved for Medullary Thyroid is because there were no other treatments for that type of cancer (making the approval process much more rapid). Phase 3 trials for renal cell are expected to begin sometime this year.
Who should take the drug:
I know that folks are excited, but Cabo is not for everyone (hah – I sound like a commercial!). The drug can be tough, perhaps more so than some of the other drugs like Inlyta and Votrient. However, Cabo works well in two subsets of patients:
- Patients with metastatic bone disease;
- Heavily pre-treated patients.
Chris falls into the second category.
Heavily pre-treated? Is this like a bad laundry stain? What the heck does that mean?
Heavily pre-treated refers to patients who have tried many different treatments but haven’t been successful. In other words, Chris, you’ve failed us one too many times. You’re like the fifth-year senior of cancer patients – and this is your truck driving school drug. (Fortunately, you’re doing great with it!)
Dr. Hammers told us that they believe that adding a c-MET inhibitor, as they have done with Cabo, somehow makes the VEGF inhibition work in patients who previously didn’t respond to other treatments like Sutent and Inlyta. That’s one of the reasons that they are trying the drug in lots of cancers where VEGF inhibition had previously been ruled out. So, for a patient who didn’t respond at all to a VEGF inhibitor like Sutent or Votrient as well as to an m-TOR inhibitor such as Afinitor, Cabo would then be a good choice to try. But only after the other drugs had been ruled out. If you responded well to Sutent, but failed after a year or so, Inlyta would still be a better second line choice.
I’m not even going to respond to that. For those of you who understand what Dena is talking about, you deserve this blog post. For folks like me who prefer their blogs jargon-free: If you’ve tried everything else and nothing has worked, then give Cabo a try.
How to get access to the drug:
- For patients with bone mets, the first and best way to get the drug is through the clinical trial that is being run at Mass General in Boston. As I mentioned earlier, Exelixis is also planning to open phase 3 trials sometime this year, which should open up more locations around the country. Hopefully these trials will give lots of people access to the drug.
- For heavily pre-treated patients like Chris, who don’t qualify for the drug in trial, the other option is to have your doctor write a prescription for Cometriq in the off-label setting.
Just so Chris doesn’t have to interrupt me – “off-label” means that an FDA-approved drug is being used to treat a disease for which it is not approved. Since Cabo/Cometriq has been approved for thyroid cancer but hasn’t been approved for kidney cancer, we’re getting the drug “off-label.”
Note: Chris just suggested that an alternative way to access the drug is to get it on-label – that is, get thyroid cancer. I will point out that we decided against this option ourselves.
The downside to off-label usage, however, is that insurance might not cover the drug – and it’s an expensive drug. The cost of the drug is $10,700 per month. So the insurance question is a big one, though there may be financial assistance available too. What we are considering, if our appeal weren’t to work, is selling our children to a sweatshop in Southeast Asia for a year or two. (What? It builds character.)
The drug is only available through one pharmacy in the country, a specialty pharmacy called Diplomat Pharmacy Services. So if your doctor is willing to write the prescription, you’ll work through Diplomat to get the drug. They are amazing and will help you through the process. The folks at Exelixis were also fantastic.
The bottom line is this: I still would encourage folks who can qualify for the drug through a clinical trial to do so. Off-label is not the ideal method – aside from the insurance issues, I believe in the FDA process. Trials give us the ability to know correct dosing, to manage and mitigate side effects, and determine when and how drugs should be used. But for people like us who really have no other option, it is good to know that there is a way to get the drug now. For some, as Chris previously said, Cabo may indeed be a miracle drug.