Eight four-week cycles of the phase-II trial of the new Celgene drug CC-4047 are now complete, and overall results are great. M-spike dropped again this month from 1.0 to 0.9, just a third of the high of 2.7 at the start of the trial. YAY! IgG is virtually unchanged, and Lambda free-light chains (FLC) are up a little but so are Kappa chains, and the ratio is actually a bit higher (better).
White cell and red cell counts are mostly unchanged, also good. Blood pressure, which was about 150/80 two months ago, was down to about 122/58 this month, probably because Dr. L has reduced my dosage of dexamethasone (dex) from 20 mg once weekly to 12 mg. That 12-mg dosage will continue for the ongoing ninth cycle. The entire protocol as prescribed by Dr. L is detailed in a previous post.
Here are some related links:
|My Myeloma||A discussion of my myeloma, not very technical.|
|My Treatment History||Not technical.|
|My Test Charts||Graphic displays of several key test results over time.|
|My Test Result Table||Best with a wide browser window. Very "technical."|
Side effects of the two key drugs, CC-4047 and dexamethasone, are discussed in a previous post.
Dexamethasone affects (increases) the level of glucose in blood, which is not good. Therefore, although I am not a diabetic, I occasionally use a blood glucose meter. In March, when I was taking 40 mg of dex, I measured blood glucose at roughly half-hour intervals on "dex day," and again several days later when the dex had worn off. In May, when taking 20 mg of dex, I measured it again on dex day. Last Monday was dex day once more, like all Mondays, and I made those measurements after taking 12 mg of dex the night before. Here is a chart that shows the results for 40 mg, 20 mg, 12 mg, and no dex. It's a busy chart, but the bottom line is: 12 mg of dex last Monday resulted in blood glucose levels at least as high as they were with 20 mg of dex last May 19, almost five months ago. That was a surprise to me but not to Dr L, see the first item below.
Some subjects that came up:
- It appears that a person's sensitivity to dexamethasone increases with use. Therefore, after a time, a lower dosage of dex will produce much the same effect as a higher dosage did previously. We were discussing side effects when Dr L mentioned this, so I do not know if that also applies to the anti-myeloma benefit of dex.
- I asked whether or not it was time to harvest stem cells against the eventuality of a stem cell transplant. Dr L responded that the CC-4047 phase-II trial protocol does not provide for the interruption required for a harvest, so I guess I will wait until the trial is over. I'm OK with that - the trial will not end for me as long as it continues to reduce my counts or hold them steady, and there is NO chance that I will want a transplant until CC-4047 fails to do that.
- Long-term dex usage can cause avascular necrosis of the bone, which is bone death attributable to insufficient blood supply. Most commonly this occurs in the hip, at the head of the femur, but it can happen in other places. I asked if I was a candidate and Dr L said it was possible, though I got the idea that I'm not really into "long-term" yet after only eight months. Further, she did not indicate that the risk was very high. I would like to think that my highly-active lifestyle might help too, but we did not discuss that.
- I asked about the half-life of myeloma cells, and she thought that it would be a property of a person's particular myeloma and would vary a great deal from one individual to another, though probably measured in months in most cases.
- The half-life of normal plasma cells is also quite variable. They are responsive to threats perceived by the body, and a few of them even become "memory B cells," which live for a very long time and retain patterns for the immunoglobulins required to neutralize the threats they have seen.
- We did not discuss this, but I believe that researchers at Johns Hopkins have identified some of these "memory B cells" as the wacko and hard-to-kill progenitors of new myeloma cells.
- Dr L recommended the flu shot and suggested November as the best time to get it. Since the shot has a limited period of effectiveness, November constitutes a balancing of the risk in the fall versus the risk in the spring.
- The Myeloma group at Mayo is moving from the Gonda Building to the Mayo Building on November 1.
- She asked about muscle weakness, particularly in the shoulders, upper arms, and quads. I am not having any problems, except that it takes an hour longer now to finish a marathon. I'll get back to my resistance exercises and try to quantify any other muscle losses.
- CC-4047 seems to be less "myelosuppressive" than Revlimid, which means that it does not harm the cells of the bone marrow so much and therefore does not suppress red and white cell counts as much. In my case there is only a barely-noticeable difference attributable to the CC-4047/dexamethasone trial.
- We discussed nifuroxazide, the subject of a recent article in Blood Journal. It's a 40-year-old antibiotic, used especially in Europe, for treatment of certain types of diarrhea. Researchers in Boston have recently discovered that it can selectively kill myeloma cells in the lab, though no studies have been done with real live humans yet. I learned of this from Beating-Myeloma, and I think it was new to Dr L. She cautioned that it's still a long way from actual use by patients, of course. Nevertheless, I suppose that if I were at the end of the treatment road and nothing else was working, I'd want to try it.
- My blood pressure has been a bit high in some of the most-recent Mayo visits, though it wasn't this time. I supposed that it should be a little higher for a person whose heart rate is low. The person needs as much blood as anyone else, and the heart doesn't have as many opportunities to pump it, so it has to pump harder on each beat, hence higher pressure. I was unable to convince her, though, because there are so many other variables and, as she said, blood pressure is more a function of the blood vessels than the heart.
|Test||Jul 24||Aug 22||Sep 16||Oct 16||Remarks|
|M-spike g/dL||1.1||1.0||1.0||0.9||Best tumor measure|
|IgG mg/dL||1360||1040||1180||1130||Variation is normal|
|L FLC mg/dL||3.30||3.57||2.64||3.14||Free light chains|
|Calcium mg/dL||9.7||9.3||9.7||9.6||Below 10.2 is best|
|Creat mg/dL||1.0||1.3||1.0||1.1||Kidney, lower is better|
|HGB g/dL||14.3||13.8||13.6||13.8||Hemoglobin, a bit low|
|RBC M/uL||4.17||3.99||3.90||3.97||Red cell count, low|
|WBC K/uL||4.7||4.4||5.3||4.4||White cells, normal|
Red cell count and hemoglobin are on the low edge. I will continue to try to improve those numbers those with sublingual B-12 for another month, but it doesn't seem to make a difference.
Meanwhile I just ran another marathon and life is good.
|The graph here shows results from 40, 20, 12, and 0 mg dex. Results from 20 mg (May) and 12 mg (Oct) are very similar, presumably because my system became more sensitive to dex in the interim. Click to enlarge.|