Background In the Phase 3 POSEIDON study, 1L T+D+CT demonstrated statistically significant improvements in PFS and OS (OS HR 0.77; 95% CI 0.65-0.92; p=0.0030; mFU 34.9 mo in censored pts) vs CT alone in pts with mNSCLC. D+CT showed a statistically significant improvement in PFS and a positive trend for OS improvement vs CT that did not reach significance (OS HR 0.86; 95% CI 0.72-1.02; p=0.0758). Here we report an updated exploratory analysis of OS, and histology and mutational status subgroups, after a mFU of ~4y.
9016 Background: MYSTIC, an open-label, Ph3 trial of first-line D (anti-PD-L1) ± T (anti-CTLA-4) vs platinum-based CT, showed an improvement in OS with D vs CT in pts with tumor cell PD-L1 expression ≥25% (PD-L1 TC ≥25%; HR 0.76 [97.54% CI 0.56–1.02], p = 0.036). Exploratory analyses showed bTMB was a predictive biomarker for OS with D±T vs CT. We report further exploratory analyses of OS according to PD-L1 and bTMB. Methods: Immunotherapy/CT-naïve pts with mNSCLC were randomized (1:1:1) to D, D+T or CT. bTMB levels (mut/Mb) were evaluated with the GuardantOMNI platform (Guardant Health), and PD-L1 TC expression with the VENTANA PD-L1 (SP263) IHC assay. Results: D improved OS vs CT in pts with PD-L1 TC ≥25% across bTMB levels (PD-L1 TC ≥25%/bTMB≥20 HR 0.79 [95% CI 0.45, 1.39]; PD-L1 TC ≥25%/bTMB < 20 HR 0.64 [95% CI 0.45, 0.90]). In contrast, D+T improved OS vs CT in pts with bTMB≥20 across different PD-L1 TC expression levels (Table; PD-L1 TC ≥25%/bTMB≥20 HR 0.44 [95% CI 0.23, 0.84]; PD-L1 TC < 1%/bTMB≥20 HR 0.42 [95% CI 0.17, 0.97]). Additional cutoffs and outcomes in subgroups defined by both biomarkers will be presented. Conclusions: These exploratory analyses from MYSTIC support PD-L1 TC expression as an appropriate predictive biomarker for OS with D vs CT, while suggesting bTMB as a predictive biomarker for OS with D+T in mNSCLC. These biomarkers appear to be independent and both may be important for mNSCLC treatment decisions. Interpretation of these data may be limited by small sample sizes; further investigations are warranted. Clinical trial information: NCT02453282. [Table: see text]
Background: In MYSTIC (NCT02453282), an open-label, Phase 3 study of first-line D (anti-PD-L1) ± tremelimumab vs platinum-based CT in mNSCLC, while not statistically significant, a clinically meaningful improvement in OS was seen with D vs CT in pts with tumour cell PD-L1 expression ≥25% (PD-L1 TC ≥25%; HR 0.76 [97.54% CI 0.56–1.02], p=0.036). Here we describe subsequent treatment patterns and explore the effect of subsequent IO on the OS outcome with D vs CT. Methods: IO/CT-naïve mNSCLC pts were randomised to D (20 mg/kg i.v. q4w until disease progression) or CT (up to 6 cycles; pemetrexed maintenance permitted). In-study crossover from CT to D was not allowed. For D vs CT, the primary endpoint was OS in pts with PD-L1 TC ≥25%. Three statistical models were employed in exploratory analyses to evaluate the effect of subsequent (post-study) IO on the OS data: the rank preserving structural failure time (RPSFT) method, the inverse probability of censoring weighting (IPCW) method, and a 2-stage method. Results: 163 and 162 pts with PD-L1 TC ≥25% were randomised to D and CT, respectively. At data cut-off (04 Oct 2018), 44.8% of pts in the D arm and 58.6% of pts in the CT arm had received subsequent treatment (Table). Most pts started subsequent treatment within 2 mos of discontinuing study treatment. Among pts who received subsequent treatment, IO was administered to 10/73 (13.7%) pts in the D arm and 64/95 (67.4%) pts in the CT arm; most commonly nivolumab. Using the 2-stage method, which was the most appropriate for evaluating the effect of subsequent IO, OS was improved with D vs CT (HR 0.66 [95% CI 0.51, 0.86]).TableLBA4Durvalumab (n=163)Chemotherapy (n=162)Pts who received study treatment, n (%)161 (98.8)153 (94.4)→Pts who discontinued study treatment136 (83.4)152 (93.8)→Pts remaining on study treatment25 (15.3)1 (0.6)Pts who received any subsequent treatment, n (%)73 (44.8)95 (58.6)→Immunotherapy10 (6.1)64 (39.5)→→Nivolumab3 (1.8)50 (30.9)→→Pembrolizumab4 (2.5)11 (6.8)→→Atezolizumab2 (1.2)3 (1.9)→→Durvalumab02 (1.2)→→Tremelimumab01 (0.6)→→Other immunotherapy1 (0.6)2 (1.2)→Cytotoxic chemotherapy70 (42.9)58 (35.8)→Other systemic therapies*Excluding immunotherapy and cytotoxic chemotherapy.18 (11.0)18 (11.1)Denominators for percentages are the number of pts randomised.* Excluding immunotherapy and cytotoxic chemotherapy. Open table in a new tab Denominators for percentages are the number of pts randomised. Conclusions: In the MYSTIC study, a markedly higher proportion of pts in the CT arm than in the D arm received subsequent IO, which may have confounded the primary OS outcome. An exploratory analysis showed increased OS benefit with first-line D vs CT after adjusting for the effect of subsequent IO. Editorial acknowledgement: Medical writing support, which was in accordance with Good Publication Practice (GPP3) guidelines, was provided by Samantha Holmes, PhD, of Cirrus Communications (Macclesfield, UK), an Ashfield company, and was funded by AstraZeneca. Legal entity responsible for the study: AstraZeneca PLC. Funding: AstraZeneca. Disclosure: N. Reinmuth: Personal fees: BMS, Roche, AstraZeneca, Takeda, Novartis, Boehringer Ingelheim, MSD, Lilly, outside the conduct of the study. B.C. Cho: Grants/research support: Novartis, AstraZeneca, Yuhan, ONO/BMS, MSD, Bayer; Advisor/honoraria fees: AstraZeneca, Roche, Boehringer Ingelheim, Yuhan, BMS, MSD, Novartis; Speaker's bureau fees: AZ, BMS, MSD, Novartis. J. Schneider: Stock/other ownership: AstraZeneca, Bristol-Myers Squibb, Pfizer, Celgene, Loxo; Consulting/advisory role: Takeda Oncology; Research funding: AstraZeneca, Bristol-Myers Squibb. F.A. Shepherd: Consultancy/advisory role: Lilly, AstraZeneca, Boehringer Ingelheim, Merck Serono; Stock ownership: Lilly, AstraZeneca; Honoraria: Lilly, AstraZeneca, BMS, Roche/Genentech, Merck Sharp & Dohme, Merck Serono, Boehringer Ingelheim; Research funding: Lilly, Pfizer, BMS, AstraZeneca, Roche Canada, Merrimack. S. Peters: Personal fees: AbbVie, Amgen, AZ, Bayer, Biocartis, BI, BMS, Clovis, Daiichi Sankyo, Debiopharm, Eli Lilly, F. Hoffmann-La Roche, Foundation Medicine, Illumina, Janssen, MSD, Merck Serono, Merrimack, Novartis, Pharma Mar, Pfizer, Regeneron, Sanofi, Seattle Genetics, Takeda; Non-financial support: Amgen, AZ, BI, BMS, Clovis, F. Hoffmann-La Roche, Illumina, MSD, Merck Serono, Novartis, Pfizer. S.L. Geater: Research grants/funding: AstraZeneca, Roche, Novartis. T. Van Ngoc: Research funding: AstraZeneca, GSK, Novartis. M.C. Garassino: Personal fees: Eli Lilly, Boehringer Ingelheim, Otsuka Pharma, AstraZeneca, Novartis, BMS, Roche, Pfizer, Celgene, Incyte, Inivata, Takeda, Tiziana Science, Clovis, Merck Serono, Bayer, MSD, GSK. F. Liu, D. Clemett, P. Thiyagarajah, M. Ouwens, U. Scheuring: Full-time employment: AstraZeneca. N. Rizvi: Advisory boards: AbbVie, AZ, BMS, EMD Serono, Genentech, GSK, Janssen, Lilly, Merck, Novartis, Pfizer, Regeneron, Neogenomics, Oncomed, Gritstone, Bellicum; Equity: Oncomed, Gritstone, Bellicum, ARMO; Royalties: PGDX (patent filed by MSKCC). All other authors have declared no conflicts of interest.
To investigate whether the location and extent of the CT hyperdense artery sign (HAS) at presentation affects response to IV alteplase in the randomized controlled Third International Stroke Trial (IST-3).
Methods:
All prerandomization and follow-up (24–48 hours) CT brain scans in IST-3 were assessed for HAS presence, location, and extent by masked raters. We assessed whether HAS grew, persisted, shrank, or disappeared at follow-up, the association with 6-month functional outcome, and effect of alteplase. IST-3 is registered (ISRCTN25765518).
Results:
HAS presence (vs absence) independently predicted poor 6-month outcome (increased Oxford Handicap Scale [OHS]) on adjusted ordinal regression analysis (odds ratio [OR] 0.66, p < 0.001). Outcome was worse in patients with more (vs less) extensive HAS (OR 0.61, p = 0.027) but not in proximal (vs distal) HAS (p = 0.420). Increasing age was associated with more HAS growth at follow-up (OR 1.01, p = 0.013). Treatment with alteplase increased HAS shrinkage/disappearance at follow-up (OR 0.77, p = 0.006). There was no significant difference in HAS shrinkage with alteplase in proximal (vs distal) or more (vs less) extensive HAS (p = 0.516 and p = 0.580, respectively). There was no interaction between presence vs absence of HAS and benefit of alteplase on 6-month OHS (p = 0.167).
Conclusions:
IV alteplase promotes measurable reduction in HAS regardless of HAS location or extent. Alteplase increased independence at 6 months in patients with and without HAS.
Classification of evidence:
This study provides Class I evidence that for patients within 6 hours of ischemic stroke with a CT hyperdense artery sign, IV alteplase reduced intra-arterial hyperdense thrombus.
'/%3e%3c/defs%3e%3cpath fill='%23012169' d='M0 0h10080v5040H0z'/%3e%3cpath stroke='%23fff' stroke-width='.6' d='m0 0 6 3m0-3L0 3' clip-path='url(%23b)' transform='scale(840)'/%3e%3cpath stroke='%23e4002b' stroke-width='.4' d='m0 0 6 3m0-3L0 3' clip-path='url(%23c)' transform='scale(840)'/%3e%3cpath stroke='%23fff' stroke-width='840' d='M2520 0v2520M0 1260h5040'/%3e%3cpath stroke='%23e4002b' stroke-width='504' d='M2520 0v2520M0 1260h5040'/%3e%3cg fill='%23fff'%3e%3cuse xlink:href='%23d' x='2520' y='3780'/%3e%3cuse xlink:href='%23a' x='7560' y='4200'/%3e%3cuse xlink:href='%23a' x='6300' y='2205'/%3e%3cuse xlink:href='%23a' x='7560' y='840'/%3e%3cuse xlink:href='%23a' x='8680' y='1869'/%3e%3cuse xlink:href='%23e' x='8064' y='2730'/%3e%3c/g%3e%3c/svg%3e)
'%3e%3cpath fill='%23012169' d='M0 0v30h60V0z'/%3e%3cpath stroke='%23fff' stroke-width='6' d='m0 0 60 30m0-30L0 30'/%3e%3cpath stroke='%23C8102E' stroke-width='4' d='m0 0 60 30m0-30L0 30' clip-path='url(%23b)'/%3e%3cpath stroke='%23fff' stroke-width='10' d='M30 0v30M0 15h60'/%3e%3cpath stroke='%23C8102E' stroke-width='6' d='M30 0v30M0 15h60'/%3e%3c/g%3e%3c/svg%3e)
