OK. Let’s get real. Readers are asking, “How long will access to the new myeloma therapies featured at ASH help me live?
Tricky question. Answering is like trying to hit a moving target. Complicating things are combination therapies. Even after a new myeloma drug is approved, experts still won’t know how combining the new drug with existing therapies might work. Earlier posts about how surprisingly well Kyprolis is working in combination with a number of different drugs is a prime example of this.
It also highlights the difficulties in figuring out what works best. As we’ve learned from following some maintenance therapies, slowing myeloma down at first doesn’t always translate into improved overall survival (OS) statistics.
Difficult or not, I’m going to try! There are some consistent numbers to work with. For example, Onyx’s Kyprolis, Celgene’s pomalidomide and Millennium’s MLN9708 all show a median progression free survival (PFS) benefit of between 8 months and a year when used as a single agent. As single agents, Kyprolis helps around 25% of relapsed, heavily pretreated patients, while pom and 9708’s numbers are a bit higher, between 40-50%.
But Kyprolis is already matching or exceeding those numbers when inserted into some combination therapies. My guess is the same will also apply to the other two.
So… Let’s play the odds. If your current combination therapy is failing, and you have become resistant (refractory) to Velcade and/or Revlimid, here is what a reasonable patient might have a right to expect.
Remember, median means one half of patients fall below that number and one half above. And don’t forget we are comparing PFS numbers, not overall survival stats, because reliable OS stats aren’t readily available yet. I’ll try and convert PFS to OS in a bit. So here goes…
I’m going to make the assumption that the relapsed patient I describe above has a 125% chance at least one of them will help; meaning most patients should respond to at least one of these drugs. Considering different combinations–and that a patient is working with a specialist that has access to them and is willing to try them all–I’m going to assume that two of the three drugs will show at least some benefit in our make-believe patient.
Sticking with the numbers, we need to concede that although both drugs may work, one of them probably won’t work very long. So I’m going with one drug works longer than the median PFS and one less.
Based on my shaky and arbitrary assumptions, I believe a heavily pretreated, refractory patient can reasonably expect to live between one and two years longer now that Kyprolis, pom and 9708 are available.
A year and a half doesn’t sound like much, especially when you are THE patient! But that is a HUGE gain by oncology standards. And I’m not done.
Combinations. It’s all about combinations. Recalculating! One or more combo therapies should add some additional time. So let’s factor-in an additional six bonus months, bringing our patient’s total PFS up to two years.
Now remember that PFS isn’t overall survival. But unless something unexpected happens–which can and does in long-lived myeloma patients–our subject isn’t going to die while their cancer is under control. Which means they should/could live even longer, right?
One reason median numbers aren’t better is patients do die from (but not limited to) pneumonia and other infections, blood clots to the lung, heart and brain, heart attacks and heck, old age. These unfortunate events drag-down the numbers. In this case, I would think using median numbers actually favor our patient. If he or she can stay otherwise healthy–and they make it to the median two years–our test patient could live for for years longer.
Let’s add it all up. Based on what I just described, two years is a conservative expectation. It could be a lot more. Sure beats the current 8-10 months!
Confused? Depressed? Never going to read one of my posts again? Don’t be!
Remember what I said about hitting “a moving target?” If you can live an additional two+ years, chances are several other new combination drugs will be available by then. And several of those may help the new drugs work longer. Heck, they may even allow a drug that used to work (Velcade and/or Revlimid or Thalomid) come back into play.
Get the idea?
Yes. At some point our patient’s immune system may not be able to recover and/or their myeloma may mutate into an aggressive type that proves unstoppable. But like Jim Bond, a well known, long-lived myeloma survivor, our patient may recover from a number of close calls and live 20 or more years, too!
I’m not the first to try and figure all of this out. As a matter of fact, I believe that most of this is already baked into the stats many oncologists quote a newly diagnosed patient today when they tell them, “You could live a decade or more.”
That said, please remember that we aren’t statistics! I’ve written about how important that affirmation here before! After all, numbers like these are nothing more than logical guesses, based on what has happened to others in the past, and what someone thinks could happen to you in the future.
All of this is a good reason to follow news about experimental therapies. One or more of them might just help save your life someday. You wouldn’t be the first patient to suggest something new to their oncologist and have them look into it and exclaim: “The numbers look pretty good. Let’s give it a try!”
Feel good and keep smiling! Pat
NOTE: I have corrected math from my original post, conceding that %150 amd 125% aren’t real numbers. Just figures of speech. A way to help explain why I think many of us could live several years longer–or more–thanks to the development of these three new myeloma therapies: Kyprolis (carfilzomib), pomalidomide and MLN9708.