This story reported on a phase 1b trial of a drug called vistusertib, which is being tested in tandem with chemotherapy on ovarian and lung cancer patients whose disease had been unresponsive to other treatments. The purpose of the trial was to establish dosing and get a preliminary look at the drug’s effectiveness. Findings were published in the Annals of Oncology.
Echoing the optimistic framing of a news release, this Newsweek story focused on the fact that some patients who took their drug saw their tumors shrink, including a quote calling the findings “very encouraging.” It also overlooked discussion of potential harms and and didn’t caution readers that tumor shrinkage doesn’t necessarily lead to longer survival.
Nearly half of women in the U.S. diagnosed with ovarian cancer don’t live more than five years. Targeted therapies like this one — which are designed to attack specific vulnerabilities in cancer cells — are being tested to treat cases that recur or resist standard treatment with surgery or chemotherapy.
While targeted therapies are an important area of research, the public shouldn’t be oversold on early-phase trials or led to think that tumor shrinkage portends a cure.
There’s no discussion of the potential cost of this drug, which is likely to be significant due to the high cost of new cancer therapies. As a comparison, a recently approved new cancer drug also made by Astra Zeneca, Imfinzi, costs $180,000 a year.
The story said that over “half of patients with ovarian cancer and over a third with lung cancer saw their tumors shrink“ and the combination of therapies “also stopped the cancer growing for almost six months.”
That doesn’t provide readers with much information — by how much did their tumors shrink, especially when compared to the control group? Same with the suppression of cancer growth — how did that compare to the control group?
Most importantly, the story didn’t address overall survival. Does the drug help women live longer? As we’ve explained, tumor shrinkage and progression-frees survival are “surrogate markers” and no guarantee of a longer life.
Potential harms were not mentioned. According to the study, the most common side effects were fatigue, nausea, anemia, and diarrhea.
The story never lets readers know that phase 1b trials such as this one are primarily conducted to assess the safest dose for patients as well as establish adverse event rates. While some aspects of the drug’s benefit were tested (see quantify benefits, above), the trial is still too small and preliminary to make any big claims about the drug working.
The story did not exaggerate the prevalence of these cancers, though it would have been useful to provide some numbers on how many women develop metastatic ovarian cancer that doesn’t respond to current treatments.
There was no information about conflicts of interest. The study was funded by drugmaker AstraZeneca with support from the UK-based Institute of Cancer Research (ICR) and The Royal Marsden. Some of the researchers reported ties with AstraZeneca.
The story correctly mentions that treatment options for ovarian cancer are limited, but doesn’t spell out what is available. In addition to chemotherapy, surgery is commonly performed to remove ovarian tumors, and other targeted therapies are under study.
The story mentioned a larger trial with 140 ovarian cancer patients that will test the drug’s effectiveness versus chemotherapy alone, with results “expected later this year.” This is enough information that a reader can infer that it’s not available yet.
However, the story didn’t explain what scientific and regulatory hurdles would have to be overcome for this drug to become available.
The story didn’t put this trial into context. Multiple other targeted therapies have been tested in phase 1 and 2 trials for ovarian cancer, with results that warranted further study. This seems to be one more avenue of research.
The story drew from but did not rely on an enthusiastic ICR news release, which said the drug combination had “exciting” results.