Clinical procedures
toxicity, toxicities, neutropenia, reductions or interruptions
DISEASE PROGRESSION, NEUTROPENIA, EVENT, EVENTS, PATHOLOGY
Patients received palbociclib 125 mg once daily for 21 consecutive days, followed by 7 days off in 28-day cycles. Palbociclib should be swallowed whole and taken with food. Dose reductions or interruptions were established according to the drug brochure. Hematological grade 3 or 4 toxicity on day 1 required a delay of one further week, or longer, up to recovery ≤grade 2. In the event of grade 3 neutropenia lasting more than one week or recurrent grade 3 on day 1, dose reduction was considered. Two dose-level reductions, up to 100 and 75 mg per day, were allowed, whereas a further dose reduction would lead to treatment cessation. In the case of non-hematological grade 3 toxicities, treatment had to be postponed up to recovery ≤grade 2, and palbociclib was then resumed with an inferior dose level. Treatment with palbociclib was continued until any of the following events occurred: disease progression, unacceptable toxicity, withdrawal of consent, a requirement for a third dose reduction, or if the patient was considered by the sponsor or investigator to be non-compliant with the requirements of the protocol. Central pathology confirmation was required before the accrual. Central radiology review was also compulsory, but it was planned to be performed at the time of the end of the study. Appropriate imaging tests usually by CT scan and, occasionally, by MRI were performed every 8 weeks and anonymously uploaded to a web-based imaging platform.