ASCO: Sorafenib nieuwe oplossing voor resistente schildklierkanker
ArrayDe kinase remmer sorafenib remt uitgezaaide gedifferentieerde schildklierkanker nadat het niet meer reageert op standaard radioactief jood, zo blijkt uit de DECISION trial. Progressie-vrije overleving (PFS) werd bijna verdubbeld met sorafenib (Nexavar), bij een gemiddelde van 10,8 maanden versus 5,8 met placebo (p <0,0001), Marcia Brose, MD, PhD, van de Abramson Cancer Center in Philadelphia, en collega’s gevonden.Tumoren krompen met ten minste 30% in 12% van de sorafenib-behandelde patiënten in vergelijking met minder dan 1% in de placebogroep (p <0,0001), zo melden onderzoekers op de American Society of Clinical Oncology vergadering.
Progression-free survival (PFS) came in nearly double with sorafenib (Nexavar), at a median of 10.8 months versus 5.8 with placebo (P<0.0001), Marcia Brose, MD, PhD, of the Abramson Cancer Center in Philadelphia, and colleagues found.
Tumors shrank by at least 30% in 12% of the sorafenib-treated patients compared with less than 1% in the placebo group (P<0.0001), the researchers reported here at the American Society of Clinical Oncology meeting.
The findings should be practice changing given the few good options for patients with these more aggressive thyroid cancers, commented Gregory Masters, MD, of the Helen F. Graham Cancer Center in Newark, Del. “There have been a lot of phase II trials looking at targeted therapy showing some activity but there’s no standard of care,” he said. No new drugs have been approved for this form of thyroid cancer in 40 years.
Differentiated thyroid cancer accounts for about 85% of thyroid cancers, and about 5% to 15% of those develop resistance to radioactive iodine.
A few extra months of PFS would be meaningful for symptomatic cases, Masters suggested, although the several thousand dollar price tag per month may inform the clinical strategy.
For asymptomatic cases that aren’t progressing rapidly, “there might be an argument for saying can we delay the treatment another year,” Masters said. “You may get the same benefit next year when symptoms start, without a whole year of expense.”
Further studies are needed to pinpoint which patients might benefit most and what the role might be for other targeted therapies, he noted.
The phase III DECISION trial included 417 patients (median age 63; 52% female) with advanced (96% metastatic) differentiated thyroid cancer that had progressed within the prior 14 months on radioactive iodine. They were randomized to twice daily dosing with 400 mg sorafenib or placebo, with crossover allowed at disease progression.
For the primary endpoint of PFS assessed every 8 weeks by independent radiologic review using modified RECIST 1.0, sorafenib was associated with a hazard of 0.58 for progression or death compared with placebo (95% CI 0.45–0.75).
The overall survival data wasn’t mature, according to the researchers. Seventy percent of placebo patients started open-label sorafenib.
Stable disease was maintained at least 6 months in 54% of patients on sorafenib versus 34% with placebo.
Side effects were consistent with what was expected from prior sorafenib trials.
The most common treatment-emergent adverse events with sorafenib arm included hand-foot skin reaction, diarrhea, alopecia, rash or desquamation, fatigue, weight loss, and hypertension.
One death in each arm was attributed to the study drug.