Celgene's Abraxane Under Fire in NEJM Letter
Saltz has now taken aim at another drug -- Celgene's (CELG - Get Report) Abraxane, which was recently approved for the treatment of pancreatic cancer and is also approved for breast and lung cancer.
Saltz and colleague Dr. Peter Bach penned a letter published in this week's New England Journal of Medicine, raising concerns about the risk-benefit of Abraxane relative to the added cost of its use in pancreatic cancer patients.
Here's the full text of the Saltz-Bach letter (nab-Paclitaxel is the scientific name for Abraxane):
The article by Von Hoff et al. (Oct. 31 issue)1 is entitled "Increased Survival in Pancreatic Cancer with nab-Paclitaxel plus Gemcitabine." This title strikes us as inappropriately rosy, given the modest benefits and substantial toxic effects observed. The addition of nab-paclitaxel increased the median survival by 1.8 months, or 55 days. The chance of being alive at 2 years was increased from 4% to 9%. Meanwhile, an additional 10% of patients had grade 3 (severe) fatigue. Grade 2 fatigue (moderate, not relieved by rest) and duration of fatigue are not mentioned. Grade 3 (severe) neuropathy was increased by 16%. No data on grade 2 (moderate) neuropathy are presented. No data on the out-of-pocket costs of the nab-paclitaxel are provided, even though negative financial consequences represent another source of "toxicity" and a driver of bankruptcies. In this study, the incremental cost of nab-paclitaxel was around $25,000 on the basis of Medicare reimbursement rates. A more neutral title, such as "Nab-Paclitaxel plus Gemcitabine in Pancreas Cancer," might help avoid an imbalanced perception of the study findings.
Also in this week's NEJM, Dr. Daniel Von Hoff and his colleagues, authors of the Abraxane pancreatic cancer study, respond:
Celgene said Abraxane sales in 2013 totaled $649 million, a 52% year-over-year increase. The company does not break out Abraxane sales by cancer indication.
The authors reply: In response to Saltz and Bach: the benefit of therapy with nab-paclitaxel plus gemcitabine needs to be evaluated in the context of innovations for advanced pancreatic cancer and other cancer treatments. Since 1997, more than 30 large trials involving patients with pancreatic cancer have been conducted, and only 3 have shown a statistically significant improvement in survival, as compared with gemcitabine alone. The survival curves in our study separate early and continue to diverge. It is important to note that the rate of long-term survival was increased at 1 year (35% vs. 22%) and beyond. Our relative increase in median survival of 26.9% (hazard ratio, 0.72) is similar to results observed in studies that led to drug approvals by the Food and Drug Administration from January 2009 through November 2013 across nine tumor types, with a mean hazard ratio of 0.70 (range, 0.44 to 0.82) and a mean relative increase in median survival of 27.6% (range, 14.3 to 67.2). The rates of grade 1 or 2 fatigue with the combination therapy were increased by 5 percentage points, from 36% to 41%. A detailed analysis of neuropathy was presented, showing that grade 2 occurred in 14% of patients and grade 3 in 17% of patients, predominantly late in their treatment. For patients who received the average 4 months of treatment, rates of grade 2 and grade 3 neuropathy were 6% and 7%, respectively. Neuropathy was rapidly reversible, and for nearly half the patients, treatment resumed after interruption. On that basis, this regimen can be built on as the backbone for combinations to enhance this initial advance. For the incremental treatment cost, analyses must be viewed in the context of the total cost of care, including drugs, drug administration, growth factors, supportive care, and duration of illness. To address these factors, a pharmacoeconomic analysis of this complex multinational study is needed. The cited Washington State study involving cancer patients in which younger patients with local disease were at increased risk for bankruptcy is less relevant for patients with metastatic pancreatic cancer, in whom the median age at diagnosis is more than 70 years.
Saltz doesn't appear to be a fan of Abraxane in pancreatic cancer but then, he says nothing about eliminating its use at Sloan Kettering in his NEJM letter, either. Saltz's criticism of Abraxane is another reminder, however that the controversy over drug pricing and reimbursement isn't going anyway.