Understanding Truqap:

Truqap is a first-in-class oral pan-AKT inhibitor blocking all three AKT isoforms (AKT1, AKT2, AKT3) in the PI3K/AKT/mTOR signaling pathway. The CAPItello-291 trial established Truqap + fulvestrant as the standard of care for HR+ HER2-negative metastatic breast cancer with PIK3CA, AKT1, or PTEN alterations after progression on endocrine therapy. Tumor genetic testing identifies patients most likely to benefit.

How Truqap works:

The PI3K/AKT/mTOR signaling pathway drives breast cancer cell growth, survival, and resistance to endocrine therapy. Activating alterations in PIK3CA (encoding PI3K-alpha), AKT1 (encoding AKT1), or loss-of-function PTEN alterations occur in approximately 30–50% of HR+ HER2-negative metastatic breast cancer — driving endocrine therapy resistance.

Capivasertib inhibits all three AKT isoforms (AKT1, AKT2, AKT3) — blocking downstream signaling that drives cell survival, proliferation, and endocrine resistance. Combined with fulvestrant (selective estrogen receptor degrader), the regimen produces significant progression-free survival improvement vs fulvestrant alone in tumors with PI3K/AKT pathway alterations. The CAPItello-291 trial established this as standard of care after progression on endocrine therapy.

Form and use:

Truqap 200 mg tablets. 400 mg twice daily (2 tablets BID) on an intermittent dosing schedule: 4 days on, 3 days off, repeated weekly. Combined with fulvestrant intramuscular injection (500 mg on days 1, 15, and 29; then every 28 days). Continue until disease progression or unacceptable toxicity. Take with or without food. Renal and hepatic dose adjustments per labeling. Monitor blood glucose (hyperglycemia common), CBC, comprehensive metabolic panel.

Generic availability:

No generic Truqap. Other targeted therapies for HR+ HER2-negative metastatic breast cancer: CDK4/6 inhibitors (palbociclib/Ibrance — generic now, ribociclib/Kisqali, abemaciclib/Verzenio), mTOR inhibitor everolimus (Afinitor — generic now, substantially cheaper PI3K/AKT/mTOR pathway alternative), PI3K inhibitor alpelisib (Piqray — for PIK3CA-mutant breast cancer specifically, not pan-AKT like Truqap), selective estrogen receptor degraders (fulvestrant — generic now, elacestrant/Orserdu for ESR1-mutant disease, camizestrant pipeline). Standard endocrine therapy: aromatase inhibitors (anastrozole, letrozole, exemestane — generic), tamoxifen (generic). For BRCA-mutated HR+ HER2-negative breast cancer: Lynparza (olaparib), Talzenna (talazoparib). For HR+ HER2-low: trastuzumab deruxtecan (Enhertu) per DESTINY-Breast06. Antibody-drug conjugates (sacituzumab govitecan/Trodelvy for HR+ progression). Standard chemotherapy backbones (taxanes, anthracyclines, antimetabolites — all generic). NCCN guidelines guide treatment selection by mutation status and prior therapy history.

Warnings:

**Hyperglycemia (very common — monitor fasting blood glucose at baseline and during treatment; treat with diabetes therapy as needed), severe cutaneous adverse reactions (rash, erythema multiforme, SJS/TEN — discontinue and seek care for severe skin reactions), diarrhea (very common, sometimes severe — supportive care; dose hold or reduction for severe cases), embryo-fetal toxicity.** Other: nausea, vomiting, decreased appetite, fatigue, mouth ulcers, urinary tract infection, cytopenias. Drug interactions: strong CYP3A4 inhibitors (azoles, clarithromycin, ritonavir, grapefruit) increase capivasertib — caution; strong CYP3A4 inducers (rifampin, phenytoin, carbamazepine, St. John’s wort) reduce efficacy — avoid; concurrent diabetes therapy may need adjustment for hyperglycemia control.