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Palbociclib + aromatase inhibitor (palbociclib-aromatase-inhibitor)

Pfizer Inc. · preclinical active Small molecule

Palbociclib + aromatase inhibitor (generic name: palbociclib-aromatase-inhibitor) is a Palbociclib + aromatase inhibitor Small molecule drug developed by Pfizer Inc.. It is currently in preclinical development.

Palbociclib + aromatase inhibitor

Palbociclib combined with an aromatase inhibitor is a CDK4/6 inhibitor plus hormone therapy used for hormone receptor-positive, HER2-negative advanced breast cancer. Palbociclib blocks cell cycle progression while the aromatase inhibitor reduces estrogen production, providing complementary mechanisms to slow cancer growth. This combination significantly improves progression-free survival compared to hormone therapy alone.

Likelihood of approval
8% vs 5% industry baseline
If approved by FDA: likely 2036–2040
Steps remaining: Phase 1 → Phase 2 → Phase 3 → NDA/BLA submission
Confidence: Low
Why this estimate
  • Baseline preclinical → approval rate +5.0pp
    Industry-wide preclinical drugs reach approval ~5% of the time (BIO/Informa 2023 industry benchmark across all therapeutic areas).
  • Big-pharma sponsor +3.0pp
    Pfizer Inc. is a top-20 pharma sponsor — historical approval rates run ~3pp above average due to scale, regulatory experience, and trial-design quality.
Predicted approval windows by jurisdiction (conditional on FDA approval)
Regulator Country Likely year Lag vs FDA
FDA US 2036–2040
EMA EU 2037–2041 +0.7 yr
MHRA GB 2037–2041 +0.7 yr
Health Canada CA 2037–2042 +0.9 yr
TGA AU 2037–2042 +1.2 yr
PMDA JP 2037–2042 +1.5 yr
NMPA CN 2038–2043 +2.3 yr
MFDS KR 2037–2042 +1.4 yr
CDSCO IN 2037–2043 +1.8 yr
ANVISA BR 2038–2043 +2.3 yr

Hover any row for the lag rationale. Lag estimates are reduced when the drug has FDA Breakthrough or EMA PRIME designation (sponsors file globally in parallel).

Estimate based on the BIO/Informa industry phase transition rates plus per-drug modifiers for therapeutic area, sponsor type, FDA designations, mechanism, and trial design. Per-jurisdiction lags from Tufts CSDD international approval studies. Not investment, clinical or regulatory advice. Methodology: /methodology#likelihood.

At a glance

Generic namepalbociclib-aromatase-inhibitor
SponsorPfizer Inc.
Drug classPalbociclib + aromatase inhibitor
ModalitySmall molecule
Therapeutic areaOncology
Phasepreclinical

Mechanism of action

Cancer cells grow by moving through distinct phases of the cell cycle, controlled by proteins called CDK4 and CDK6. Palbociclib works by blocking these proteins, essentially putting cancer cells in a holding pattern and preventing them from progressing to the next division phase. This slows or stops the cancer's ability to multiply. Aromatase inhibitors work by a different mechanism—they reduce the body's estrogen production. Many breast cancers depend on estrogen to grow, so lowering estrogen starves these cancer cells of a critical growth signal. By using both drugs together, they attack the cancer from two angles: stopping cell division directly while also removing one of the main fuels that drives growth. This combination is particularly effective in hormone receptor-positive, HER2-negative breast cancers, which have receptors on their surface that respond to estrogen. The pairing of a direct cell-cycle inhibitor with hormone suppression has proven more effective than either approach alone, helping delay disease progression and improve outcomes for patients with advanced breast cancer.

Approved indications

No approved indications tracked.

Pipeline indications

Common side effects

No common side effects on file.

Key clinical trials

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

Frequently asked questions about Palbociclib + aromatase inhibitor

What is Palbociclib + aromatase inhibitor?

Palbociclib + aromatase inhibitor (palbociclib-aromatase-inhibitor) is a Palbociclib + aromatase inhibitor drug developed by Pfizer Inc..

How does Palbociclib + aromatase inhibitor work?

Palbociclib + aromatase inhibitor

Who makes Palbociclib + aromatase inhibitor?

Palbociclib + aromatase inhibitor is developed by Pfizer Inc. (see full Pfizer Inc. pipeline at /company/pfizer).

What is the generic name of Palbociclib + aromatase inhibitor?

palbociclib-aromatase-inhibitor is the generic (nonproprietary) name of Palbociclib + aromatase inhibitor.

What drug class is Palbociclib + aromatase inhibitor in?

Palbociclib + aromatase inhibitor belongs to the Palbociclib + aromatase inhibitor class. See all Palbociclib + aromatase inhibitor drugs at /class/palbociclib-aromatase-inhibitor.

What development phase is Palbociclib + aromatase inhibitor in?

Palbociclib + aromatase inhibitor is in preclinical.

Related

Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing