Maintenance capecitabine and bevacizumab versus bevacizumab alone after initial first-line bevacizumab and docetaxel for patients with HER2-negative metastatic breast cancer (IMELDA): a randomised, open-label, phase 3 trial
Mené sur 284 patientes atteintes d'un cancer métastatique du sein HER2-, cet essai randomisé international de phase III évalue l'efficacité, du point de vue de la survie sans progression, et la toxicité de l'ajout de capécitabine au bevacizumab en traitement d'entretien après un traitement initial combinant bevacizumab et docétaxel
Background : Longer duration of first-line chemotherapy for patients with metastatic breast cancer is associated with prolonged overall survival and improved progression-free survival. We investigated capecitabine added to maintenance bevacizumab after initial treatment with bevacizumab and docetaxel in this setting. Methods : We did this open-label randomised phase 3 trial at 54 hospitals in Brazil, China, Egypt, France, Hong Kong, India, Italy, Poland, Spain, and Turkey. We enrolled patients with HER2-negative measurable metastatic breast cancer; each received three to six cycles of first-line bevacizumab (15 mg/kg) and docetaxel (75—100 mg/m2) every 3 weeks. Progression-free patients were randomly assigned with an interactive voice-response system by block (size four) randomisation (1:1) to receive either bevacizumab and capecitabine or bevacizumab only (bevacizumab 15 mg/kg on day 1; capecitabine 1000 mg/m2 twice per day on days 1—14, every 3 weeks) until progression, stratified by oestrogen receptor status (positive vs negative), visceral metastases (present vs absent), response status (stable disease vs response vs non-measurable), and lactate dehydrogenase concentration (≤1·5 vs >1·5 × upper limit of normal). Neither patients nor investigators were masked to allocation. The primary endpoint was progression-free survival (from randomisation) in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT00929240. Findings : Between July 16, 2009, and March 7, 2011 (when enrolment was prematurely terminated), 284 patients received initial bevacizumab and docetaxel; 185 (65%) were randomly assigned (91 to bevacizumab and capecitabine versus 94 to bevacizumab only). Progression-free survival was significantly longer in the bevacizumab and capecitabine group than in the bevacizumab only group (median 11·9 months [95% CI 9·8—15·4] vs 4·3 months [3·9—6·8]; stratified hazard ratio 0·38 [95% CI 0·27—0·55]; two-sided log-rank p<0·0001), as was overall survival (median 39·0 months [95% CI 32·3—not reached] vs 23·7 months [18·5—31·7]; stratified HR 0·43 [95% CI 0·26—0·69]; two-sided log-rank p=0·0003). Results for time to progression were consistent with those for progression-free survival. 78 (86%) patients in the bevacizumab and capecitabine group and 72 (77%) in the bevacizumab only group had an objective response. Clinical benefit was recorded in 92 (98%) patients in the bevacizumab alone group and 90 (99%) in the bevacizumab and capecitabine group. Mean change from baseline in global health score did not differ significantly between groups. Grade 3 or worse adverse events during the maintenance phase were more common with bevacizumab and capecitabine than with bevacizumab only (45 [49%] of 91 patients vs 25 [27%] of 92 patients). The most common grade 3 or worse events were hand—foot syndrome (28 [31%] in the bevacizumab and capecitabine group vs none in the bevacizumab alone group), hypertension (eight [9%] vs three [3%]), and proteinuria (three [3%] vs four [4%]). Serious adverse events were reported by ten (11%) patients in the bevacizumab and capecitabine group and seven (8%) patients in the bevacizumab only group. Interpretation : Despite prematurely terminated accrual and the lack of information about post-progression treatment, both progression-free survival and overall survival were significantly improved with bevacizumab and capecitabine compared with bevacizumab alone as maintenance treatment. These results might inform future maintenance trials and current first-line treatment strategies for HER2-negative metastatic breast cancer. Funding : F Hoffmann-La Roche.