Real-World Safety Profile of Generic Palbociclib in Hormone Receptor–Positive, HER2-Negative Metastatic Breast Cancer: A Prospective Observational Study in Iraq”

• Rawaa Abdulzahra Mohammed Hussein

  Oncology Teaching Hospital, Medical City Complex, Baghdad, Iraq

• Abeer Abdulhadi Rashid

  Mustansiriyah University, College of Pharmacy, Baghdad, Iraq

• Zahraa Matheel Nasir

  Oncology Teaching Hospital, Medical City Complex, Baghdad, Iraq

Background: Breast cancer accounts for the highest incidence of cancer among Iraqi women. Generic Palbociclib has recently become available, yet there remains a lack of real-world clinical equivalence data.

Methods: A prospective observational study carried out between September 2024 & April 2025 at the oncology teaching hospital in the medical city complex with (175) participants included those on generic palbciclib with fluvestrant or Aromatase inhibitor(AI). All participants were completed the study without any dropouts.

Results: Neutropenia was common in both AI (88.3%) and Fluvestrant (87.2%) groups. Increase in Anemia was more marked in the Fulvestrant group (93.6%) than in AI (63.3%) with p-value <0.001), and the same for hair loss p=0.005; 46.8% and urticaria (p =0.019 , 19.1%). The mean age in each of the groups was similar (50.8 years vs 51.6 years), indicating that age did not have a significant effect on association found. As all patients had ECOG performance status of 0 to 1, performance status was not considered in the regression analysis because of lack of variability.

Conclusion: Generic Palbociclib safety profile is consistent with initial studies and historical data and it’s tolerability is confirmed under-resourced settings.

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