Phase III inavolisib + palbociclib + fulvestrant in PIK3CA-mutated, endocrine-resistant HR+/HER2- mBC. FDA-approved Oct 2024; final OS HR 0.67 (NEJM 2025).
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Trial slides shared by KOLs at SABCS 2023 / ASCO 2025 / NEJM 2025. Click any image to expand. OCR text extracted via AWS Textract.
Highest-engagement tweets about this trial, ranked by KOL discussant count (replies + quote-tweets). Replies in green, quote-tweets in blue. Wall Street, stock-promo, and non-substantive replies excluded.
🔥 Big Win in HR+/HER2– Breast Cancer! Final #INAVO120 results at #ASCO25 show OS benefit with INAVO + PALBO + Fulvestrant in PIK3CA-mutated, endocrine-resistant ABC: ✅ OS: 34.0 vs 27.0 mo ✅ HR 0.67 | p = 0.019 ✅ INV-PFS: 17.2 vs 7.3 mo ✅ ORR: 62.7% vs 28% ✅ TTC delay: ~2 https://
Full text of INAVO120 abstract below 🙂👇. Check the tweet below for analysis @ASCO #ASCO25 https://t.co/BFQN3ULXh3 https://t.co/5VTfN5tGfM
#BreastCancer #OncoTwitter #PrecisionOncology #PIK3CA @ASCO #ASCO25 @OncoAlert A 24-month landmark analysis, if 50% of controls vs. 65% of INAVO patients survived, NNT = 1/(0.65–0.50) = ~7 patients to prevent one death
wouldn't change current indication though..
#BreastCancer #OncoTwitter #PrecisionOncology #PIK3CA @ASCO #ASCO25 @OncoAlert Demonstrating survival gains in advanced breast cancer (ABC) is notoriously difficult—this is a landmark for PI3K-targeted therapy.
Will need to see ❓crossover ❓PIK3CA ⛔️ use in control
INAVO120 OS Benefit: 7-month median (OS)(34.0 vs. 27.0 mo; HR 0.67, p=0.019) in a high-risk, endocrine-resistant. Robust PFS & Response: Inv PFS doubled (17.2 vs. 7.3 mo), with ORR >60% vs. 28% in controls, s/o tumor
Nick Turner presents OS results from INAVO120. Adding inavo to 1L fulv/palvo for high-risk PIK3CAm HR+/HER2- MBC improved PFS (17 vs 7 m) & OS (34 vs 27 mo), though low crossover to alpelisib (10%). Toxicities non-negligible. Concomitant @NEJM publication: https://t.co/Ugi320uOqL
#SABCS23 Highlights w/ @hoperugo on HR+ #breastcancer - #NATALEE - #MONARCH3 - #INAVO120 - #TB01 Full discussion: - https://t.co/jZrRZsOfeq - https://t.co/ovqFoUtlwT - Also on “Oncology Brothers” podcast #MedTwitter #OncTwitter #bcsm @SABCSSanAntonio @TargetedOnc https://t
Breast Cancer Highlights from #ASCO24 w/ @ErikaHamilton9 - #RxPonder - #postMONARCH - #INAVO120 - #DB06 - #EMERALD Full Int: - https://t.co/ukNyzlPC8Y - https://t.co/Q0WZyfiGBl - Also on the “Oncology Brothers” podcast #bcsm @ASCO #OncTwitter #MedTwitter @TargetedOnc http
#INAVO120, which led to the approval of inavolisib for HR+/HER2- MBC, is now published in @NEJM. Strong data, with doubling of PFS & ORR by adding inavo to fulv/palbo among high-risk patients (with PIK3CA mut & early recurrence). Non-negligible toxicities. https://t.co/Z8bXVAs4Zp
Important to see OS benefit. A theme for @ASCO #ASCO25 is vital need of defining X-over therapy/therapy at PD. In INAVO120, crossover was variable; 85% chemo but only 35% got ADC, 5% got PIK3CA inhibitor, 39% more ET. Likely important for SERANA-6 and DB-09 trials, too. https:
INAVO120 is a Phase III, double-blind, randomized trial that established inavolisib (Itovebi, oral PI3Kα inhibitor) plus palbociclib and fulvestrant as a new standard for patients with PIK3CA-mutated, HR+/HER2- endocrine-resistant locally advanced or metastatic breast cancer. The triplet doubled median PFS and produced a statistically significant 7-month median OS improvement — rare for post-CDK4/6 PI3K-targeted combinations. The FDA approved the regimen on October 10, 2024.
On October 10, 2024, the FDA approved inavolisib in combination with palbociclib and fulvestrant for endocrine-resistant, PIK3CA-mutated, HR-positive, HER2-negative, locally advanced or metastatic breast cancer. Approval based on INAVO120 PFS results; FDA-approved companion diagnostic for PIK3CA mutation testing required.
Approval date: October 10, 2024
Population: Patients with PIK3CA-mutated (centrally confirmed), HR+/HER2-, endocrine-resistant locally advanced or metastatic breast cancer.
Interventions: Inavolisib + palbociclib + fulvestrant versus placebo + palbociclib + fulvestrant. Mandatory baseline glucose monitoring and prophylactic mouthwash per labeling.
Endpoints: Primary: investigator-assessed PFS (ITT). Key secondary: OS. Other: ORR, DoR, safety.
Primary PFS analysis (NEJM 2024): median PFS 15.0 months (95% CI 11.3-20.5) with inavolisib triplet vs 7.3 months (95% CI 5.6-9.3) with placebo doublet (HR 0.43; 95% CI 0.32-0.59; p<0.0001) — doubling of median PFS. Final OS analysis (NEJM 2025): median OS 34.0 vs 27.0 months (HR 0.67; 95% CI 0.48-0.94; p=0.019) — statistically significant 7-month median OS improvement.
Hyperglycemia, stomatitis/mucositis, diarrhea, and ocular toxicity occurred more frequently with inavolisib than placebo. Mandatory baseline glucose assessment and prophylactic mouthwash recommended per FDA labeling. No new safety signals beyond known PI3Kα-class effects. Rates of treatment discontinuation due to AEs were manageable with appropriate prophylaxis.
Paolo Tarantino summarized the practice-defining OS readout: “Nick Turner presents OS results from INAVO120. Adding inavo to 1L fulv/palvo for high-risk PIK3CAm HR+/HER2- MBC improved PFS (17 vs 7 m) & OS (34 vs 27 mo), though low crossover to alpelisib (10%). Toxicities non-negligible.” In a separate post he flagged the NEJM publication, noting “Strong data, with doubling of PFS & ORR by adding inavo to fulv/palbo among high-risk patients (with PIK3CA mut & early recurrence). Non-negligible toxicities.” Harold Burstein widened the lens to the crossover question that recurs across the HR+ field: “Important to see OS benefit. A theme for @ASCO #ASCO25 is vital need of defining X-over therapy/therapy at PD. In INAVO120, crossover was variable; 85% chemo but only 35% got ADC, 5% got PIK3CA inhibitor, 39% more ET,” adding this is “Likely important for SERANA-6 and DB-09 trials, too.” Suyog Akhade tabulated the win directly: “OS: 34.0 vs 27.0 mo,” “HR 0.67 | p = 0.019,” “INV-PFS: 17.2 vs 7.3 mo,” “ORR: 62.7% vs 28%.”