Palbociclib is an inhibitor of cyclin-dependent kinases (CDK) 4 and 6. Cyclin D1 and CDK4/6 are downstream of signaling pathways that lead to cellular proliferation. Palbociclib has been shown to reduce the cellular proliferation of estrogen receptor (ER)-positive breast cancer by blocking the progression of the cell from G1 into the S phase of the cell cycle.

Description

Palbociclib is an inhibitor of cyclin-dependent kinases (CDK) 4 and 6. Cyclin D1 and CDK4/6 are downstream of signaling pathways that lead to cellular proliferation. Palbociclib has been shown to reduce the cellular proliferation of estrogen receptor (ER)-positive breast cancer by blocking the progression of the cell from G1 into the S phase of the cell cycle. 

The mean maximum observed concentration (Cmax) of Palbociclib is generally observed between 6 to 12 hours (Tmax) following oral administration. The mean absolute bioavailability of Palbociclib after an oral 125 mg dose is 46%. A Steady-state is achieved within 8 days following repeated once-daily dosing. Palbociclib undergoes hepatic metabolism in humans. Feces is the major route of excretion, with 74.1% and 17.5% of the dose recovered in feces and urine respectively. The majority of the material is excreted as metabolites.

Presentation

    Palbolib 125 Capsule: Each capsule contains Palbociclib INN 125 mg.

Indications

    Palbociclib is indicated for the treatment of adult patients with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative advanced or metastatic breast cancer in combination with:
    • An aromatase inhibitor as initial endocrine-based therapy in postmenopausal women or in men; or
    • Fulvestrant in patients with disease progression following endocrine therapy.

Dosage & Administration

    Palbociclib capsules are taken orally with food in combination with an aromatase inhibitor or fulvestrant.
    • Recommended starting dose: 125 mg once daily taken with food for 21 days followed by 7 days off treatment.
    • Dosing interruption and/or dose reductions are recommended based on individual safety and tolerability.

Contrainidications

    None.

Warning & Precautions

    Pregnancy: Palbociclib can cause fetal harm when administered to a pregnant woman. Females of reproductive potential should have a pregnancy test prior to starting treatment with Palbociclib and should be advised to use effective contraception during treatment with Palbociclib and for at least 3 weeks after the last dose.
    Nursing mothers: Women should be advised not to breastfeed during treatment with Palbociclib and for 3 weeks after the last dose.
    Pediatric use: The safety and efficacy of Palbociclib in pediatric patients have not been studied.
    Geriatric use: No overall differences in the safety or effectiveness of Palbociclib were observed between geriatric patients (≥65 years of age) and younger patients.
    Hepatic Impairment: No dose adjustment is required in patients with mild or moderate hepatic impairment (Child-Pugh classes A and B). For patients with severe hepatic impairment (Child-Pugh class C), the recommended dose of Palbociclib is 75 mg once daily for 21 consecutive days followed by 7 days off
    treatment to comprise a complete cycle of 28 days.
    Renal Impairment: No dose adjustment is required in patients with mild, moderate, or severe renal impairment (CrCl >15 ml/min).

    There is no known antidote for Palbociclib. The treatment of an overdose of Palbociclib should consist of general supportive measures.

Side effects

    The most common adverse reactions (incidence ≥10%) are neutropenia, infections, leukopenia, fatigue, nausea, stomatitis, anemia, alopecia, diarrhea, thrombocytopenia, rash, vomiting, decreased appetite, asthenia, pyrexia.

Drug interaction

    CYP3A Inhibitors: Avoid concurrent use of Palbociclib with strong CYP3A inhibitors (e.g. Itraconazole). If the strong inhibitor cannot be avoided, reduce the Palbociclib dose.
    CYP3A Inducers: Avoid concurrent use of Palbociclib with strong CYP3A inducers (e. g. Ifampin, Modafinil).
    CYP3A Substrates: The dose of sensitive CYP3A4 substrates (Midazolam) with narrow therapeutic indices may need to be reduced when given concurrently with Palbociclib.

Use in special groups

    Pregnancy: Palbociclib can cause fetal harm when administered to a pregnant woman. Females of reproductive potential should have a pregnancy test prior to starting treatment with Palbociclib and should be advised to use effective contraception during treatment with Palbociclib and for at least 3 weeks after the last dose.
    Nursing mothers: Women should be advised not to breastfeed during treatment with Palbociclib and for 3 weeks after the last dose.
    Pediatric use: The safety and efficacy of Palbociclib in pediatric patients have not been studied.
    Geriatric use: No overall differences in the safety or effectiveness of Palbociclib were observed between geriatric patients (≥65 years of age) and younger patients.
    Hepatic Impairment: No dose adjustment is required in patients with mild or moderate hepatic impairment (Child-Pugh classes A and B). For patients with severe hepatic impairment (Child-Pugh class C), the recommended dose of Palbociclib is 75 mg once daily for 21 consecutive days followed by 7 days off
    treatment to comprise a complete cycle of 28 days.
    Renal Impairment: No dose adjustment is required in patients with mild, moderate, or severe renal impairment (CrCl >15 ml/min).

Packing

    Palbolib 125 Capsule: Each box contains 21 capsules in Alu-Alu blister pack.