Polatuzumab vedotin, manageable safety profile, and pharmacist involvement

Polatuzumab vedotin is a CD79b-targeted antibody-drug conjugate that preferentially
delivers a potent anti-mitotic agent monomethyl auristatin E to B-cells, which results in
the killing of malignant B-cells (1).
The most commonly reported adverse reactions in diffuse large B-cell lymphoma
patients treated with Polatuzumab vedotin plus R-CHOP were: peripheral neuropathy
(52.9 %), nausea (41.6 %), neutropenia (38.4 %) and diarrhea (30.8 %), while in the group
of patients treated with combination with bendamustine and rituximab (BR) neutropenia
(45.7 %), diarrhea (35.8 %), nausea (33.1 %) and thrombocytopenia (32.5 %), anemia (31.8
%) and peripheral neuropathy (30.5 %) (1).
Polatuzumab vedotin is subject to additional monitoring, labeled with a black inverted
triangle. Rarer adverse reactions will be visible after longer period, in a wider population (2).
Pharmacists should evaluate patients for appropriateness of therapy prior to initiation
as well as recommend prophylactic medications to mitigate toxicity. Patients receiving
concomitant strong CYP3A4 inhibitors should be monitored more closely for signs of
toxicities, because there is potential interaction between the MMAE component of polatuzumab vedotin and strong CYP3A4 inhibitors/inducers (3).
Pharmacists must be up-to-date when new drugs enter the market, so they need to know
all potential adverse reactions. Polatuzumab vedotin belongs to the category of additional monitoring drugs so it is very important the pharmacist to be monitoring those
adverse reactions and to report them to the regulatory authorities.