Pertuzumab represents the first in a new class of targeted therapeutics known as HER dimerisation inhibitors. We conducted a phase Ib study to determine the maximum-tolerated dose, the dose limiting toxicities (DLT), and pharmacokinetic (PK) interaction of docetaxel when administered in combination with pertuzumab. Initially, two dose levels of docetaxel (60 and 75 mg m-2) were explored in combination with a fixed dose of 1050 mg of pertuzumab; then two dose levels of docetaxel (75 and 100 mg m-2) were explored in combination following a fixed dose of 420 mg of pertuzumab with a loading dose of 840 mg. Both drugs were administered intravenously every 3 weeks. The latter dose of pertuzumab was allowed after an amendment to the original protocol when phase II data suggesting no difference in toxicity or activity between the 2 doses became available. Two patients out of two treated at docetaxel 75 mg m-2in combination with pertuzumab 1050 mg suffered DLT (grade 3 diarrhoea and grade 4 febrile neutropaenia). Two out of five patients treated at docetaxel 100 mg m-2in combination with pertuzumab 420 mg with a loading dose of 840 mg suffered DLT (grade 3 fatigue and grade 4 febrile neutropaenia). Stable disease was observed at four cycles in more than half of the patients treated and a confirmed radiological partial response with a >50% decline in PSA in a patient with hormone refractory prostate cancer were observed. There were no pharmacokinetic drug-drug interactions. The recommended phase II dose of this combination was docetaxel 75 mg m-2and 420 mg pertuzumab following a loading dose of 840 mg.

Additional Metadata
Keywords Docetaxel, HER dimerisation inhibitors, Pertuzumab, Phase I
Persistent URL dx.doi.org/10.1038/sj.bjc.6604043, hdl.handle.net/1765/35101
Citation
Attard, G., Kitzen, J.J.E.M., Blagden, S.P., Fong, P.C., Pronk, L.C., Zhi, J., … de Jonge, M.J.A.. (2007). A phase Ib study of pertuzumab, a recombinant humanised antibody to HER2, and docetaxel in patients with advanced solid tumours. British Journal of Cancer, 97(10), 1338–1343. doi:10.1038/sj.bjc.6604043