The results were announced at a medical meeting, which usually means the data has not been through the level of peer review used by leading medical journals and that key information may have been withheld pending journal publication. Also the trial was halted early, which may increase the odds that the results were a fluke and that if the trial had continued as intended the final results might be different than the interim numbers presented.The early trial stoppage was mentioned, but not the possible significance of that.
Medical meeting presentations often fail to include enough detail to allow solid judgments about the real significance of highlighted results.
The story does not include any estimate of the cost of the drug, but the treatment is still experimental, so it is not surprising that there is no firm estimate of the drug’s price. The story does note the high costs of other recently approved drugs to treat advanced prostate cancer… and that cost may be an issue for this product as well.
This story reports the absolute survival numbers of 15 months for advanced prostate cancer patients who received the new drug and a steroid vs. 11 months for those given a placebo and a steroid. However, it reports only the average survival figures. With many new cancer drugs, it appears that certain patients get most of the benefit, while most patients get little or no benefit, perhaps because of genetic or metabolic differences. The story should have addressed this issue.
Also, while the story notes that the drug has been tested only in patients with advanced disease who have run out of treatment options, it goes on to dangle the hope that the drug “will lead to much longer survival when studied in patients with early-stage disease.” Will it? The statement is premature. No one knows if other types of patients will benefit from this treatment because it has not been tested in them.
Some harms were mentioned, but oddly the story then referred to this hormone therapy not causing harms associated with chemotherapy. The story does not mention other harms linked to hormone therapy, such as osteoporosis, fractures, diabetes, and heart disease. We aren’t provided any information on these outcomes or cause of death. Since these results were presented at a medical meeting (which means it is likely the full data have not been reviewed by independent experts) and because the trial was halted early, there is much that remains unknown.
Although the story tells readers that the trial results were presented at a medical meeting, it does not make clear that such presentations are not peer-reviewed in the same way that articles in leading journals are, nor does the story tell readers how much information was provided about the trial methods and results. Presentations at meetings tend to include only fragmentary information, which often makes it difficult to know whether there were limitations, harms or other important details that were not revealed.
The story only briefly mentioned a red flag about the trial: it was halted earlier than originally planned after an interim check of the results showed a statistically significant survival advantage for patients receiving the experimental drug. The story would have been better if it had pointed out that such early termination can increase the risk of a statistical fluke. In a way, it can be like ending a race early when you see that the horse you bet on is in the lead, without knowing whether that lead would be sustained. Similarly, drugs sometimes appear to show a benefit at one point in time, but then do not show the same benefit when studied longer. A notorious case is Vioxx. It was approved in part based on data from a trial that was ended early. Longer follow up (along with the release of some withheld data) revealed a higher number of serious harms that altered the risk-benefit balance.
Readers are not told about the duration of follow-up or whether any patients were dropped from the study or could not be found for follow-up. The omissions could also affect the validity of the conclusions.
The story points out that the drug has been tested only in patients with advanced disease who have tried other treatments. However, the story expands the definition of who stands to benefit by raising hopes that future studies will show effectiveness in patients with less advanced disease, even though such trials have yet to begin. Furthermore, extending these new treatments to earlier-stage disease is problematic given the known risks for already overtreating many of these patients. The final quote that sequentially using the various new medications could further extend life is troubling because there is no evidence for this strategy–which could also be very expensive. That quote could have been challenged.
The statement that prostate cancer is second only to lung cancer as a killer of men creates a troubling comparison that obscures that fact that while most lung cancer patients die of their disease within a couple of years of diagnosis, most men diagnosed with prostate cancer ultimately die of something else after many years of life.
Although the story includes an independent expert and notes that the drug is being developed by Johnson & Johnson, it does not tell readers that the trial researcher quoted in the story has had a financial relationship with the drug’s commerical developers. Journal articles about earlier phases of research into this drug noted the researchers’ financial disclosures. The fact that such disclosures may not be included in materials distributed at medical meetings is one more reason to be wary of these presentations.
The story highlights two other drugs that were recently approved to treat patients similar to those included in this trial.
The story points out that the drug is experimental and is not available. However, it says the manufacturer intends to file for approval later this year, “raising prospects that the drug could be on the market next year.” While that statement is only a tentative prediction of what could happen, it still gives readers the impression that approval is likely, even though the full data from this trial has yet to be inspected by anyone other than the investigators. Nonetheless, we’ll give the story the benefit of the doubt on this criterion.
The story reports that this drug appears to work by blocking androgen hormones in a way that other hormone-blocking treatments don’t. However, readers are not told whether there are other similar drugs in development.
The story does not appear to be based on a news release.