Months In Arm Research Articles

Updated results from the trastuzumab deruxtecan (T-DXd) 5.4 mg/kg triplet combination of DESTINY-Gastric03 (DG-03): First-line (1L) T-DXd with fluoropyrimidine (FP) and pembrolizumab in advanced/metastatic HER2-positive (HER2+) esophageal adenocarcinoma, gastric cancer (GC), or gastroesophageal junction adenocarcinoma (GEJA).

448 Background: T-DXd is a HER2-directed antibody-drug conjugate; T-DXd 6.4 mg/kg monotherapy is approved for patients with metastatic HER2+ GC/GEJA who have received a prior trastuzumab-based regimen. Preliminary results from DG-03 Part 2 showed feasibility and promising antitumor activity with 1L T-DXd 6.4 mg/kg (arm D) or 5.4 mg/kg (arm F) with FP and pembrolizumab in patients with esophageal adenocarcinoma/GC/GEJA. T-DXd 6.4 mg/kg and FP with pembrolizumab was associated with higher than expected toxicity; alternatively, early safety data from T-DXd 5.4 mg/kg triplet combination showed a manageable safety profile. We report updated results for arm F from DG-03 Part 2 with an approximate time-matched analysis with arm D. Methods: DG-03 (NCT04379596) is a Phase 1b/2 multicenter, open-label, dose-escalation (Part 1) and -expansion (Parts 2, 3, and 4) study. In Part 2, patients with HER2+ (immunohistochemistry [IHC] 3+ or IHC 2+/in situ hybridization–positive by local testing) esophageal adenocarcinoma/GC/GEJA, irrespective of programmed cell death ligand 1 status, and no prior treatment for metastatic disease were enrolled. In arm D, patients received T-DXd 6.4 mg/kg intravenous (IV) infusion every 3 weeks (Q3W) and FP (5-fluorouracil [5-FU] 600 mg/m 2 continuous IV or capecitabine [cape] 1000 mg/m 2 twice daily [BID]) with pembrolizumab 200 mg IV Q3W; in arm F, patients received T-DXd 5.4 mg/kg IV Q3W and FP (5-FU 600 mg/m 2 continuous IV or cape 750 mg/m 2 BID) with pembrolizumab 200 mg IV Q3W.Primary endpoint was confirmed objective response rate by investigator assessment (INV) per RECIST 1.1. Secondary endpoints included duration of response by INV and progression-free survival by INV. Safety and tolerability were also assessed. Results: A time matched analysis was performed to compare the efficacy of arm D (n=43), data cut-off (DCO) October 27, 2022, and arm F (n=32), DCO May 6, 2024, given the limited follow up of the 5.4mg/kg. The median duration of follow up for the two cohorts was 4.1 months and 4.6 months for arm D and arm F, respectively. Objective response rate for arm D was 41.9% and 59.4% for arm F. Median PFS was 6.4 months (95% CI: 5.0, NC) for arm D and 5.8 months (95% CI: 5.6, NE) for arm F. At DCO, the median overall survival in both arms was not reached. Updated time matched safety and efficacy data will be provided at the time of presentation. Conclusion: The time matched analysis shows that lowering the dose of T-DXd to 5.4 mg/kg from 6.4 mg/kg and lowering the starting dose of capecitabine, did not result in decrease in efficacy of the combination of T-DXd + FP + pembrolizumab. Funding: This study is sponsored by AstraZeneca in collaboration with Daiichi Sankyo. In March 2019, AstraZeneca entered into a global development and commercialization collaboration agreement with Daiichi Sankyo for trastuzumab deruxtecan (T-DXd; DS-8201). Editorial acknowledgment: Under guidance of the authors and in accordance with Good Publication Practice, medical writing and editorial support was provided by Carmen Grimaldos, PhD, of Helios Medical Communications, part of Helios Global Group, and was funded by AstraZeneca. Clinical trial information: NCT04379596 .

Adjuvant chemotherapy or chemo-radiation in gallbladder cancer: A phase III randomized controlled study (ACCELERATE trial).

519 Background: Role of adjuvant therapy in gallbladder cancer is still evolving and no prospective trial has compared chemotherapy (ChT) alone to combination of chemotherapy and chemo-radiation (CRT). We designed this trial to answer whether adding CRT to ChT improves relapse free survival. Methods: In this open-label, multicentric, phase 3, non-inferiority academic trial, operated gallbladder cancers (R0 or R1) patients were randomized to physicians choice of ChT alone (either 6 cycles of mGemOx- Gemcitabine 900 mg/m2 and oxaliplatin 80 mg/m2 IVI days 1 and 8 every 3 weeks or GemCis- Gemcitabine 1000 mg/m2 and cisplatin 25 mg/m2 1 and 8 every 3 weeks) or 3 cycles of physicians choice of ChT (as above) followed by CRT (radiation 45Gyin 25 fractions in 5 weeks with concurrent oral capecitabine in the dose of 825 mg/m2 twice a day on days of radiation and further 2-3 cycles of mGemOx or GemCis. The primary endpoint was the relapse free survival. Planned sample size was 100 subjects in each arm. Results: Between April 2018 and January 2021, 137 patients were screened, and 94 eligible patients were randomized, 49 (52.1%) in chemotherapy alone arm (standard-arm1) and 45 (47.9%) in chemotherapy plus chemo-radiation arm (experimental-arm 2). Slow accrual led to premature closure of trial. COVID pandemic might have contributed to that. Baseline characteristics were well balanced (like, sex, presenting symptoms, ECOG PS, duration of symptoms, comorbidities, location of tumour in GB, presence of gallstone disease, and tumour markers were well balance in both groups) except that a greater number of patients had deranged baseline LFTs in arm1 and there was a trend towards higher numbers of stage IIA in arm 1. The median age was 55 years (range 27-73 years). Females constituted 32 in each group. 43 and 45 patients had ECOG PS of 0-1 in arm 1 and arm 2 respectively. One patient in arm 1 was ineligible. All had R0 resection. Incidences of dose reductions and dose delays were similar. A greater number of patients in arm 1 experienced diarrheal episodes (p=0.021) and peripheral neuropathy (0.001). 42 (85.7%) patients in arm 1 and 28 (62.2%) patients in arm completed 5-6 cycles. 18 (36.73%) and 23 (51.11%) died till last follow up. 14 (28.57%) and 20(44.44%) died because of disease progression. One patient in each arm died of toxicity. The primary end point of study, relapse free survival was not estimable in arm 1 and was 34.39 months in arm 2 (p=0.202). Median overall survival was not estimable in arm 1 and was 34.56 months in arm 2 (p=0.123). Mean RFS was 51.96 Vs 43.99 months in arm 1 and arm 2 respectively. Conclusions: This trial suggests that addition of CRT to ChT doesn’t improve outcome in resected gallbladder cancer compared to ChT alone. A larger trial is needed to address this issue. Clinical trial information: CTRI/2018/04/013218.

An open-label, randomized phase III study of early switch maintenance vs delayed second-line nivolumab in advanced stage squamous non-small cell lung cancer (NSCLC) patients after standard first-line platinum-based chemotherapy-EDEN trial GOIRC 04-2016.

As for squamous (Sq)-NSCLC, Checkmate-017 trial showed a significant overall survival (OS) improvement in favor of Nivolumab (Nivo) over Docetaxel in 2nd-line. We hypothesized that anticipating Nivo use, as early switch maintenance after 1st-line chemotherapy (CHT), might have improved survival as compared to delayed 2nd-line treatment. EDEN was an open-label, 2-arm, phase III study which randomized (1:1) stage IIIB/IV Sq-NSCLC pts non-progressive after 1st-line platinum-based CHT, to receive early Nivo as switch maintenance (Arm A) or standard best supportive care followed by 2nd-line Nivo at disease progression (Arm B). In both arms, Nivo was administered at the dose of 240mg i.v. every 2weeks until progressive disease, intolerable toxicity, or for a maximum of 2years. The primary endpoint was OS. From Sep 2017 to Aug 2020 125 patients (62 Arm A vs 63 Arm B) were randomized from 32 Italian centers. Accrual was stopped early, before the planned sample size (388 pts) was reached, because of registration of ICPIs in 1st-line. Most patients were male (79.2%), current/former smokers (93.6%), had stage IV (74.4%), performance status 0-1 (98.4%). mOS (95% CI) was 14.9 (10.4-18.6) months in arm A vs 18.8 (14.4-21.1) months in arm B (HR 1.09, 95%CI 0.74-1.62, p=0.659). In advanced Sq-NSCLC, the use of Nivo as switch maintenance after 1st-line CHT, does not improve OS compared to its use as 2nd-line. Although the optimal use of ICPIs remains in 1st-line, its role as maintenance has to be better investigated. gov: registration number: NCT03542461.

Efficacy and tolerability of single-fraction radiotherapy for spinal bone metastases in a low-middle-income country setting: a prospective study

AimsThis study aimed to evaluate the symptomatic efficacy and tolerability of three different radiotherapy (RT) regimens for patients with vertebral metastases in a low-middle-income country setting, focusing specifically on the effectiveness of single-fraction radiotherapy.MethodsConducted at the National Institute of Cancer Research and Hospital, Bangladesh, from July 1, 2020, to June 30, 2021, this prospective, non-randomized study enrolled 90 patients aged 18 to 75 years with histologically confirmed primary malignancies and vertebral metastases. Patients were allocated to one of three treatment arms: 8 Gy in a single fraction (Arm A), 20 Gy in 5 fractions (Arm B), or 30 Gy in 10 fractions (Arm C). The primary endpoint was pain response at 12 weeks, assessed by the Visual Analogue Scale and International Bone Metastases Consensus. Secondary endpoints included toxicity, measured by the Common Terminology Criteria for Adverse Events, and overall survival.ResultsPain control at 12 weeks showed no significant differences among the treatment groups, with 70% of patients in Arm A, 67% in Arm B, and 70% in Arm C experiencing either partial or complete pain relief (p = 0.95). The overall survival rates were comparable across the groups (median survival, 7 months for arms A and C, 6 months for Arm B). Skin toxicity was significantly lower in Arm A (10% incidence) compared to arms B (30%) and C (47%) (p = 0.017). There were no reports of Grade 3 or higher toxicities.ConclusionThe study confirms the efficacy and safety of single-fraction RT for spinal bone metastases, providing significant pain relief and lower skin toxicity relative to multiple fraction regimens. These results confirm the efficacy of single-fraction RT in the treatment of vertebral metastases also in resource-limited settings, suggesting its broader adoption to reduce toxicity and treatment burdens in low-middle-income countries.

Maintenance with 5-FU/LV-aflibercept after induction with FOLFIRI-aflibercept versus FOLFIRI-aflibercept until progression as second-line treatment in older adults with metastatic colorectal cancer: the AFEMA phase II randomized trial

The combination chemotherapy i.v. 5-fluorouracil (5-FU), irinotecan, and aflibercept (FOLFIRI-A) is a standard second-line treatment of metastatic colorectal cancer (mCRC). The aim was to assess maintenance treatment in second-line setting in older patients (aged ≥70 years) with mCRC. We evaluated FOLFIRI-A given for six cycles followed by maintenance with 5-FU/leucovorin (LV)-A (arm A) or FOLFIRI-A (arm B) until progression in older adults with mCRC in the AFEMA randomized, open-label, non-inferiority phase II trial (EudraCT2016-004076-21/NCT03279289). Patients aged ≥70 years who previously failed oxaliplatin-fluoropyrimidine were randomly allocated (1 : 1) to either arm A (experimental) or arm B (control). After enrolling 35 patients, the FOLFIRI dose was reduced to level 1 in both arms due to toxicity. The primary endpoint was median progression-free survival (PFS); and secondary endpoints were median overall survival, objective response rate, and safety. Non-inferiority required the upper confidence interval (CI) limit to not exceed a hazard ratio (HR) of 1.5 (one-sided α= 0.075, 80% power). A total of 170 patients were randomly allocated to arm A or arm B (n= 85 each). The median follow-up was 12.2 versus 10.9 months in arm A versus arm B. Most patients died (83.5% versus 88.2% in arm A versus arm B), mainly from disease progression. PFS non-inferiority was met (HR= 0.78, 95% CI 0.566-1.076, P= 0.131) with a median PFS of 6.1 versus 5.5 months in arm A versus arm B. Median overall survival was similar in arms A and B (12.2 and 11.5 months, respectively) (HR= 0.89, 95% CI 0.640-1.227, P= 0.467). During the maintenance phase, severe asthenia (4.5% versus 21.6%, P= 0.038), serious adverse events (SAEs) (17.8% versus 37.8%, P= 0.049), and treatment-related SAEs (6.7% versus 10.8%, P= 0.695) were reduced in arm A versus arm B. In older adults, induction with six cycles of FOLFIRI-A plus maintenance with 5-FU/LV-A was non-inferior to FOLFIRI-A until progression. Severe asthenia, SAEs, and treatment-related SAEs were reduced with 5-FU/LV-A maintenance.

Intermittent or Continuous Panitumumab Plus Fluorouracil, Leucovorin, and Irinotecan for First-Line Treatment of RAS and BRAF Wild-Type Metastatic Colorectal Cancer: The IMPROVE Trial.

To investigate whether intermittent treatment after an induction phase of first-line schedule of fluorouracil, leucovorin, and irinotecan (FOLFIRI) plus panitumumab (PAN) prevents or delays the onset of resistance and improves safety and compliance with treatment in patients with unresectable RAS/BRAF wild-type (wt) metastatic colorectal cancer (mCRC). IMPROVE (ClinicalTrials.gov identifier: NCT04425239) was an open-label, multicenter, randomized phase II noncomparative trial. Patients with unresectable RAS/BRAF wt mCRC were randomly assigned (1:1) to receive FOLFIRI plus PAN continuously until progression (arm A) or intermittently, with treatment-free intervals (arm B) until progression on treatment, toxicity, or death. The primary end point was progression-free survival on treatment (PFSot) at 12 months. Assuming a null hypothesis of median PFSot time ≤7 months and target PFSot ≥10 months, 65 patients per arm were needed to achieve 80% power and 10% type I error, according to the binomial test. Between May 2018 and June 2021, 69 patients were randomly assigned to arm A and 68 to arm B. The median number of treatment cycles was 13 in arm A and 16 in arm B. At a median follow-up of 43.2 months (IQR, 35.0-50.5), median PFSot was 11.2 and 17.5 months with 12-month PFSot rates of 45.7% and 58.5%, for arms A and B, respectively. The overall response rates were 68.1% and 61.2%, and median overall survival rates were 36.3 and 35.1 months in arms A and B, respectively. The overall rate of grade >2 skin PAN-related adverse events was 30.3% in arm A and 17.9% in arm B. Intermittent FOLFIRI plus PAN after the induction phase was feasible, and the primary end point was met with reduced toxicity while allowing patients more time off treatment.

Abstract A001: An open label, phase II trial of ERK inhibition alone and in combination with autophagy inhibition in patients with metastatic cancreatic cancer

Abstract Background: Approximately 92% of pancreatic ductal adenocarcinoma (PDAC) harbor activating mutations in the KRAS oncoprotein. Therapeutic targeting of key elements of the MAPK pathway, including RAF, MEK and ERK, have failed to yield clinical benefit in patients with metastatic PDAC. Autophagy is a putative mechanism of resistance to ERK MAPK inhibition. Hydroxychloroquine (HCQ) is an inhibitor of autophagy and functions by inhibiting acidification of lysosomes. LY3214996 is an inhibitor of ERK 1/2 and has shown anti-tumor activity in pre-clinical models of PDAC. In this study, we evaluate the clinical efficacy of LY3214996 alone and in combination with HCQ. Methods: Eligible patients had metastatic PDAC or poorly differentiated carcinoma of the pancreas. Patients had at least one, but no more than two prior lines of systemic therapy. Twelve patients were included in the safety lead-in. One patient experienced grade 3 acute kidney injury and another experienced grade 3 nausea, thus dose level -1 was chosen as the tolerable dose for combination therapy. Patients were randomized in a 1:1 fashion to receive either LY3214996 200mg PO daily + HCQ 600mg PO BID (Arm 1) or LY3214996 400mg PO daily (Arm 2). The primary endpoint was disease control rate (DCR), defined as the proportion of patients with complete responses (CR), partial responses (PR) or stable disease (SD) that persisted for at least 4 months. Secondary endpoints included overall survival (OS) and progression-free survival (PFS). Point estimates and exact binomial 95% confidence interval (CI) were used for binary endpoints and the Kaplan Meier method was used for survival analysis. With 20 subjects in each treatment arm, there is 79% power using a one-sided alpha of 0.1 to differentiate between an unacceptable DCR of 5% and a desirable DCR of 20%. Results: A total of 39 patients met criteria for analysis (20 in Arm 1, 19 in Arm 2). The DCR rate in Arm 1 was 5% and 5.3% in Arm 2. One patient in each arm had SD. No patients achieved a CR or PR. The median PFS was 1.31 months in Arm 1 (95% CI 0.79-1.77) and 1.87 months in Arm 2 (95% CI 1.64-2.36). The median OS was 2.43 months in Arm 1 (95% CI 1.34-5.77) and 4.56 months in Arm 2 (95% CI 3.08-5.67). The most frequently observed toxicities in both arms included nausea, diarrhea, elevated creatine phosphokinase (CPK), anorexia and cytopenias. Exploratory analysis using patient-derived organoids did not show evidence of synergistic anti-tumor activity of LY3214996 in combination with chloroquine. Conclusion: LY3214996 alone or in combination with HCQ did not result in clinically meaningful activity in patients with metastatic pancreatic cancer. Further studies are needed to evaluate optimal strategies for autophagy inhibition, as well as combination strategies with other ERK MAPK targets (i.e., KRAS inhibitors) to fully elucidate the role of autophagy as a driver of resistance to ERK MAPK inhibition. Citation Format: Rishi Surana, Hui Zheng, Junning Wang, Micaela Morgado, Lauren K Brais, Kirsten L Bryant, Ashwin Somasundaram, Colin D Weekes, Bruno Bockorny, Mary Linton B Peters, Andrea J Bullock, Jessica A Zerillo, Ahmed A Rattani, Hanna K Sanoff, Jeffrey W Clark, Aparna R Parikh, Matthew B Yurgelun, Anuj Patel, Robert J Mayer, James M Cleary, Peter C Enzinger, Douglas A Rubinson, Nadine J McCleary, Andrea C Enzinger, Sarah E Slater, Kimmie Ng, Thomas A Abrams, Leah Biller, Srivatsan Raghavan, Joseph D Mancias, Jonathan O Nowak, Andrew J Aguirre, Channing J Der, Brian M Wolpin, Kimberley Perez. An open label, phase II trial of ERK inhibition alone and in combination with autophagy inhibition in patients with metastatic cancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pancreatic Cancer Research; 2024 Sep 15-18; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl_2):Abstract nr A001.

Comparison between Trans-Arterial Chemoembolization Followed by Stereotactic Body Radiation Therapy and Trans-Arterial Chemoembolization Alone in BCLC Stage B Hepatocellular Carcinoma: A Pilot Study.

Both Stereotactic Body Radiation Therapy (SBRT) and Trans-arterial Chemoembolization (TACE) are now being widely used to treat advanced hepatocellular carcinoma (HCC) and can improve tumor local control rates. We aimed at evaluating the efficacy and toxicity of combining SBRT and TACE in comparison to TACE alone in unresectable HCC. 42 unresectable Barcelona Clinic Liver Cancer (BCLC) stage B HCC Child Pugh (CP) A patients were randomized to receive either: TACE alone (Arm A) or TACE followed by SBRT (Arm B). Dose prescribed was 40Gy in 5consecutive daily fractions over 1 week . We compared the local control (LC), Progression free survival (PFS), overall survival (OS) and toxicity between the two arms. 22 patients were in arm A versus 20 patients in arm B with median follow up 20 months starting recruitment from April 2021 till January 2023. Both LC, PFS were significantly better in Arm B. Complete remission (CR) rate was 54.5% and 75% in Arm A and B, respectively. Median PFS was 16 months in Arm B compared to 11 months in Arm A (p =0.003). Median OS was not reached in both arms. Both arms had comparable toxicities. Adding SBRT to TACE in advanced HCC, is safe and feasible with better efficacy in terms of LC and PFS with comparable side effects, in comparison to TACE alone.

Induction avelumab followed by chemoimmunotherapy and maintenance versus chemotherapy alone as first-line therapy in cis-ineligible metastatic urothelial carcinoma (INDUCOMAIN): a randomized phase II study

Platinum-based chemotherapy (ChT) has been the standard first-line treatment for metastatic urothelial carcinoma (mUC). The purpose of this study was to evaluate the use of induction avelumab followed by avelumab in combination with carboplatin-gemcitabine (carbo/gem) followed by avelumab maintenance. We tested the hypothesis that induction immunotherapy (IO) could enhance the response to ChT and prevent its detrimental effect on immune cells. INDUCOMAIN is a multicenter, randomized, investigator-initiated, open-label phase II study evaluating the safety and efficacy of induction avelumab before carboplatin-gemcitabine-avelumab, followed by avelumab maintenance (arm A), compared to carbo/gem (arm B). Eligibility criteria included patients with mUC, no prior systemic therapy, and ineligibility for cisplatin by Galsky criteria. Patients were stratified by the presence/absence of visceral metastasis and Eastern Cooperative Oncology Group performance status 0-1 versus 2. The primary endpoint was objective response rate (ORR). Secondary endpoints included progression-free survival (PFS), overall survival (OS), and safety. Eighty-five patients were included and randomized to arm A (n= 42) and arm B (n= 43), respectively. ORR was similar between treatment arms: 59.5% in arm A and 53.5% in arm B (P= 0.57). Fourteen patients (33%) in arm A early progressed/died before or at first response assessment, compared to three patients (7%) in arm B. Median OS was 11.1 months in arm A and 13.2 months in arm B [hazard ratio (HR) 0.91, 95% confidence interval (CI) 0.57-1.46, P= 0.69]. Median PFS was 6.9 months in arm A versus 7.4 months in arm B (HR 0.99, 95% CI 0.61-1.60, P= 0.95). Treatment-related adverse events of grade 3-4 occurred in 70.7% of patients in arm A and in 72.1% in arm B. No predictive role of programmed death-ligand 1 expression was found. The hypothesis that induction avelumab could enhance the efficacy of subsequent ChT was not proven. Administering IO alone as induction before ChT is not an adequate strategy.

Comparison between Reirradiation by Stereotactic Body Radiation Therapy and Moderately Hypofractionated Radiotherapy in Combination with Temozolomide for Treatment of Recurrent High Grade Glioma.

High grade glioma (HGG) is considered a lethal disease with a high recurrence rate. There is no standard of care in recurrent HGG. Many treatment options are present, such as resurgery, systemic therapy, and re-irradiation. Re-irradiation seems to be a promising option. In this study, we aimed at comparing the efficacy and toxicity of two re-irradiation protocols. Forty patients with recurrent HGG were randomized equally into two arms. Arm A received 30 Gy/10f/2w, and arm B received stereotactic body radiotherapy (SBRT) 30 Gy/5f/1w. Concurrent temozolamide (TMZ) was given in both arms. Median progression free survival (PFS) and overall survival (OS) were calculated, and brain MRI was done after 2 months of radiotherapy and then every 2 months, with documented toxicity using the Common Terminology of Adverse Events version 5 (CTCAE). The median follow-up time after the re-irradiation course was 11 months (range 8-15 months). The median PFS after recurrence was 6.4 months (95% CI 5.3-7.4), the median OS after recurrence was 8.6 months (95% CI 7.5-8.7), and the median total OS form date of diagnosis was 18.5 months (95% CI 17.3-19.8) among the included patients. There was a statistically significant difference in PFS favoring arm B, with a median PFS of 7.3 versus 6.2 months in arm A, with p values of 0.004. There was no statistically significant difference in in median OS (9.3 months in arm B versus 8.4 months in arm A) with p values of 0.088. All patients tolerated their treatment well, and acute and subacute G1-G2 toxicity, consisting of headache, malaise, and nausea, were recorded during and shortly after the end of the re-irradiation course. Re-irradiation in recurrent HGG by both protocols is safe and effective, with a significant improvement in PFS in SBRT arm but no significant improvement in OS.

Effect of chemotherapy/targeted therapy alone vs. chemotherapy/targeted therapy followed by radical surgical resection on survival and quality of life in patients with limited-metastatic adenocarcinoma of the stomach or esophagogastric junction: The IKF-575/RENAISSANCE phase III trial.

LBA4001 Background: The IKF-575 trial investigates the long-standing question about the role of surgical intervention in limited-metastatic gastric / esophagogastric junction cancer after systemic induction therapy. Methods: Previously untreated patients (pts) with limited metastatic disease (retroperitoneal lymph node (RPLN) metastases only or a maximum of one incurable organ site that is potentially resectable or locally controllable with or without retroperitoneal lymph nodes) received 4 cycles of FLOT, + trastuzumab if Her2+ or + nivolumab if PD-L1 positive. Pts without progression after 4 cycles were randomized to receive additional FLOT (Arm B) or radical complete surgical resection of primary and metastases followed by the same treatment (Arm A). It was planned to randomize 176 pts for which 271 pts had to enrolled. The primary endpoint was overall survival in the ITT population using Kaplan-Meier estimates. Recruitment was stopped after enrollment of 183 patients (141 patients randomized) with minimal impact on statistical power, due to a slow enrollment rate. Results: The ITT comprised 139 pts (A, 67; B, 72): 20% had RPLN metastases only, 58% organ metastases only, and 22% had both. Surgery in Arm A (ITT) was performed in 91% of pts and R0-resection rate (primary) was 82%. 30-d and 90-d mortalities in the surgery population were 3% and 8%. At least 4 additional cycles of post-op or post-randomization chemotherapy were achieved in 42% of pts in Arm A vs. 71% of pts in Arm B. The primary endpoint ovrall survival was not met due to increased early mortality in the surgery Arm leading to crossing survival curves with OS 25%- and 75%-Quantiles being 10 vs. 14 months and 65 vs. 41 months for Arms A vs. B, respectively. Pts with RPLN metastases only seemed to benefit most from the surgical approach (mOS, 30 vs. 17 months; 5y OS 38% vs. 19%; still having increased early mortality), while pts showing no response to chemo (mOS, 13 vs. 22 months) or pts with peritoneal disease (mOS, 12 vs. 19 months) derived a detrimental effect. Conclusions: The IKF-575/RENAISSANCE trial is negative but informs future research. Future protocols should focus on pts with RPLN only disease and exclude non-responding pts or those with peritoneal disease. There is a need for strategies against the early mortality caused by chemotherapy interruption. Clinical trial information: NCT02578368 .

A randomized phase II trial of 8 months of afatinib switching to osimertinib (A) versus osimertinib alone (B) as first-line treatment in advanced NSCLC patients with common EGFR mutation: YAMATO study (TORG1939/WJOG12919L).

8574 Background: NSCLC with common EGFR mutation (L858R or exon 19 deletion (Del19)) is known to originally comprise small portion of uncommon and compound EGFR variant cells including T790M-mutant ones albeit treatment-naïve. To overcome concomitant heterogeneous EGFR mutations, we planned a randomized phase II trial to assess the strategy of switching to osimertinib following 8 months of afatinib compared with osimertinib alone. Methods: YAMATO study is an open-label, multi-center, randomized phase II study. Patients with newly diagnosed stage III/IV/recurrent NSCLC harboring EGFR activating mutations (L858R or Del19) were randomized in a 1:1 ratio to receive up-front 8 months of afatinib (30 mg or 40 mg QD) followed by osimertinib (80 mg QD) (arm A) or osimertinib (80mg QD) alone (arm B) until disease progression or intolerable toxicity. The primary endpoint is 2-year progression free survival (PFS) rate with threshold rate of 22% and expected rate of 40% (one-tailed alpha of 0.1, beta of 0.2). Secondary endpoints are objective response rate (ORR), PFS, time to treatment failure, overall survival and adverse events. Results: Between May 2020 and Apr 2021, 113 patients were enrolled from 27 institutions (A/B 56/57). Patient characteristics were as follows: median ages, 73.5/71 years (range 41-85/41-92 years); proportion of males, 42.9/35.1%; EGFR mutation types, L858R/Del19 59/41% in A, 58/42% in B. The difference of two-year PFS rate was not observed statistically significant between groups (37.3% [80% CI, 29.0 to 45.5] in arm A vs 47.4% [80% CI, 38.5 to 55.7] in arm B; p=0.44; HR:1.28 [80% CI, 0.95-1.73]). The ORR was 82% in arm A and 87% in arm B. With the median follow-up of 27.5 months, median PFS was 16.8 months in arm A, and 22.2 months in arm B (HR: 1.280, p = 0.29). Severe pneumonitis occurred in 7% in arm A, most of which developed after switching to osimertinib, and 1.8% in arm B. Conclusions: YAMATO study failed to demonstrate the superiority of EGFR-TKI switching therapy of 8 months afatinib to osimertinib over osimertinib alone in terms of 2-year PFS rate in untreated advanced NSCLC patients with common EGFR mutations. Clinical trial information: 031200021 .

A randomised phase II study of extended pleurectomy/decortication preceded or followed by chemotherapy in patients with early-stage pleural mesothelioma: EORTC 1205.

The role of surgery in pleural mesothelioma remains controversial. It may be appropriate in highly selected patients as part of a multimodality treatment including chemotherapy. Recent years have seen a shift from extrapleural pleuropneumonectomy toward extended pleurectomy/decortication. The most optimal sequence of surgery and chemotherapy remains unknown. EORTC-1205-LCG was a multicentric, noncomparative phase 2 trial, 1:1 randomising between immediate (arm A) and deferred surgery (arm B), followed or preceded by chemotherapy. Eligible patients (Eastern Cooperative Oncology Group 0-1) had treatment-naïve, borderline resectable T1-3 N0-1 M0 mesothelioma of any histology. Primary outcome was rate of success at 20 weeks, a composite end-point including 1) successfully completing both treatments within 20 weeks; 2) being alive with no signs of progressive disease; and 3) no residual grade 3-4 toxicity. Secondary end-points were toxicity, overall survival, progression-free survival and process indicators of surgical quality. 69 patients were included in this trial. 56 (81%) patients completed three cycles of chemotherapy and 58 (84%) patients underwent surgery. Of the 64 patients in the primary analysis, 21 out of 30 patients in arm A (70.0%; 80% CI 56.8-81.0%) and 17 out of 34 patients (50.0%; 80% CI 37.8-62.2%) in arm B reached the statistical end-point for rate of success. Median progression-free survival and overall survival were 10.8 (95% CI 8.5-17.2) months and 27.1 (95% CI 22.6-64.3) months in arm A, and 8.0 (95% CI 7.2-21.9) months and 33.8 (95% CI 23.8-44.6) months in arm B. Macroscopic complete resection was obtained in 82.8% of patients. 30- and 90-day mortality were both 1.7%. No new safety signals were found, but treatment-related morbidity was high. EORTC 1205 did not succeed in selecting a preferred sequence of pre- or post-operative chemotherapy. Either procedure is feasible with a low mortality, albeit consistent morbidity. A shared informed decision between surgeon and patient remains essential.

A randomized, open-label phase II/III efficacy and safety study of atezolizumab in combination with FLOT versus FLOT alone in patients with gastric cancer and adenocarcinoma of the oesophagogastric junction and high immune responsiveness: The IKF633/DANTE trial, a trial of AIO in collaboration with SAKK.

TPS4184 Background: Despite recent advances, long-term survival of patients with locally advanced, operable esophagogastric adenocarcinoma (EGA) is below 50%. Immune checkpoint inhibitors in the neoadjuvant setting of this tumor type have lately been shown to increase pathological responses in all comers (IKF633/DANTE pII, KEYNOTE-585, Matterhorn), but the effect on survival is still unknown. The IKF633/DANTE pIII trial evaluates the efficacy and clinical activity of atezolizumab (ATZ) with perioperative FLOT in patients (pts) with locally advanced, resectable EGA considered having an immune-responsive profile. Methods: IKF633/DANTE is conducted as a randomized, multinational, multicenter, prospective, investigator-initiated, open label phase II/III trial. For the phase III portion, pts with histologically confirmed EGA of a clinical stage ≥cT2 and/or cN+ without evidence of distant metastases and with at least one immune response criterium (MSI, PD-L1 CPS≥1, TMB ≥10/MB or EBV+) are eligible. Pts are stratified acc. to nodal stage (cN- vs. cN+), tumor site (GEJ type I vs. GEJ type II/III vs. gastric) and PD-L1 expression levels (CPS≥5 vs. CPS<5). Pts are randomized 1:1 to receive 4 pre- and post-operative cycles FLOT/ATZ, followed by 8 cycles ATZ maintenance (Arm A) or 2x4 perioperative cycles FLOT alone (Arm B). In total, 556 pts will be enrolled, thereof 379 pts in phase III. This estimates to a recruitment time of 30 months plus 18 months follow-up for 80% statistical power and a significance level of p<0.05 (two-sided log rank test). The primary endpoint is event-free survival (EFS) with a target hazard ratio of 0.72, reflecting a clinically relevant improvement to 41.65 months in arm A. Main secondary endpoints are pCR, overall survival (OS) also in high immune-responsive subgroups (CPS ≥5/ CPS≥ 10/ MSI), R0 resection rate and safety/tolerability. In addition, a prospective biomarker study with serial circulating tumor DNA (ctDNA) analysis accompanying therapy is performed to explore the prognostic impact of ctDNA on efficacy and survival parameters, as well as on relapse incidence. Recruitment of phase III started in Aug 2023 and is still ongoing. Clinical trial information: NCT03421288 .

A randomized phase II study of gemcitabine and nab-paclitaxel compared with 5-fluorouracil, leucovorin, and liposomal irinotecan in older patients with treatment-naïve metastatic pancreatic cancer (GIANT): ECOG-ACRIN EA2186.

4003 Background: Evidence-based data is lacking to guide the care of vulnerable older adults with newly diagnosed metastatic pancreatic ductal adenocarcinoma (mPDAC) resulting in extrapolation of the treatment approach utilizing data from younger patients. EA2186 is a phase II randomized controlled trial, and the first prospective study aiming to define the optimal treatment approach for vulnerable older adults with newly diagnosed mPDAC. Methods: EA2186 enrolled vulnerable patients ≥70 years of age with histologically confirmed mPDAC, ECOG PS 0-2 and adequate organ function. Vulnerability was defined by a screening geriatric assessment (GA) demonstrating mild abnormalities in functional status, comorbidities, cognition, or age ≥80 years. Patients were randomized to Arm A: Gemcitabine (1000mg/m2) and Nab-Paclitaxel (125mg/m2) every 14 days or Arm B: 5-Fluorouracil (2400mg/m2 over 46hr) Leucovorin (400mg/m2) and Liposomal Irinotecan (50mg/m2) every 14 days. A comprehensive GA and quality of life (QOL) evaluation were completed at baseline and 3 time points. Primary endpoint was overall survival (OS); secondary endpoints included progression free survival (PFS), response rate (RR), safety, and QOL. The study had 90% power to detect a difference in median OS of 7.7 vs. 10.7 months (HR of 0.72) using a one-sided log-rank test at the 0.10 significance level. Stratification factors included age 70-74 vs ≥75, and ECOG PS 0-1 vs 2. The study met the planned futility boundary for OS at its single interim analysis (60.6% information) and was closed early by the DSMC. Results: 176 patients were enrolled at 92 US sites between 6/2020 – 10/2023, 88 patients per arm. Median age of enrolled patients was 77 (range 70-90), 49% females, 24% ECOG-0, 64% ECOG-1 and 12% ECOG-2. Majority of patients were deemed vulnerable by cognition (46%), age (36%) or co-morbidities (31.4%), with some patients meeting vulnerability criteria in multiple domains. No significant difference was seen in median OS between the arms (4.7 vs. 4.4 months in Arms A and B respectively; p = 0.72). PFS, RR, and factors contributing to early treatment discontinuation and affecting the lower-than-expected survival will be presented at the meeting. At the time of data cut off rates of ≥grade 3 toxicity was 45.6% in Arm A and 58.7% in Arm B (p = 0.10); rates of ≥grade 4 toxicity were 7.6% in Arm A vs 14.7% in Arm B (p = 0.16). Most common ≥grade 3 toxicities included anemia, neutropenia, fatigue in both Arms, and diarrhea in Arm B. Conclusions: EA2186 did not demonstrate a significant difference in efficacy or overall toxicity between two attenuated regimens tested in vulnerable older adults with mPDAC. These results provide important data to guide treatment decisions and goals of care discussions in this vulnerable patient population. Clinical trial information: NCT04233866 .

A pilot study of tazemetostat and pembrolizumab in advanced urothelial carcinoma (ETCTN 10183).

4574 Background: Mutations of COMPASS-related proteins KMT2D, KMT2C, and KDM6A are observed in 66% of advanced urothelial carcinomas (UC). In vivo, the administration of tazemetostat, an enzymatic EZH2 inhibitor (EZH2i), reduced tumor burden and enhanced the immune response in animal models of UC. We hypothesized that tazemetostat might improve response to immunotherapy in advanced UC. Methods: ETCTN 10183 (NCT03854474) is a multicenter pilot study evaluating the safety and efficacy of tazemetostat 800 mg BID+ pembrolizumab 200 mg given every three weeks for up to two years in patients (pts) with platinum-refractory (Arm A) or cisplatin/chemo-ineligible advanced UC (Arm B). The primary objective was to identify the recommended phase two dose (RP2D) of tazemetostat in combination with pembrolizumab. Secondary objectives included safety, response rate, and progression-free survival. Translational objectives included determining tumor mutational burden in COMPASS-related genes, tumor subtyping, TCR clonality, T cell infiltration, and PDL-1 expression. Results: There were no dose-limiting toxicities in the safety lead-in phase (n=6 pts), and the RP2D for tazemetostat was established at 800 mg BID. Baseline characteristics for Arm A N=12, Arm B N=13: 72% males; 96% white, 4% Black; 88% ECOG PS 0-1; 88% had bladder primary, 20% Stage III, 72% stage IV; 80% had visceral or bone metastases. The median number of cycles was 5 in Arm A (range 1-35) and 4 in Arm B (range 2-12). Treatment related G3/4 adverse events (AEs) were observed in 8 patients, most common were anemia and lymphopenia (n=2 each). Treatment related G1/2 AEs included nausea (n=6); skin and subcutaneous tissue disorders (n=3); anemia, lymphopenia, and thrombocytopenia (n=2 each). Among evaluable patients (n=10 in each arm), partial response rate was: Arm A 30%, Arm B 20%; stable disease: Arm A 30%, Arm B 30%; and progressive disease: Arm A 30%, Arm B 20%. 8 pts were on study treatment for ≥ 9 cycles (5 in Arm A, 3 in Arm B). All pts are off protocol treatment. Median progression-free survival was 3.06 (95% CI: 1.38-7.75) months for Arm A and 3.02 (95%CI: 2.4-5.65) for Arm B. Conclusions: Tazemetostat 800 mg BID and pembrolizumab combination is feasible and well-tolerated in patients with advanced UC. In this pilot study, improvement in efficacy relative to historical controls of pembrolizumab alone appears to be modest. Response in tumors with COMPASS-related mutations and EZH2 activity will be evaluated. Clinical trial information: NCT03854474 .

Abstract PO3-14-06: Immunologic features and association with prognosis in hormone receptor-positive/HER2-negative (HR+/HER2-) metastatic breast cancer (MBC) treated with chemotherapy (CT) or CDK4/6-inhibitors (CDK4/6i) + endocrine therapy (ET)

Abstract Purpose: Little is known regarding the prognostic and predictive role of tumor immunological features in HR+/HER2- MBC treated with CT or CDK4/6i+ET. Methods: The Italian KENDO phase 2 trial randomized CT-naïve patients with HR+/HER2-neg. MBC with aggressive characteristics to receive CDK4/6i+ET (arm A) or CT+/-ET (arm B). Primary endpoint was progression-free survival (PFS). A tumor sample from the primary or metastatic tumor (archived or newly-obtained) was mandatory for inclusion. In this correlative biomarker analysis, tumor-infiltrating lymphocytes (TILs) and tertiary lymphoid structures (TLS) were detected on baseline tumor samples by hematoxylin&eosin staining, while immune genomic signatures were assessed with the nCounter BC360 panel. Immune pattern at immunohistochemistry was defined as inflamed (IF), excluded (IE) or desert (ID). TILs and signatures were dichotomized (high vs. low) with the maximally-selected rank statistics (MSRS) method. Survival analyses were conducted with the Kaplan-Meier (KM) method and differences were tested with log-rank test. Hazard ratios (HR) with 95% confidence intervals (CI) were estimated with Cox regression. Significance was set at p≤0.05. Since the trial was stopped earlier due to slow accrual all analyses were exploratory. Results: Forty-nine patients were randomized, 17 (34.7%) in arm A and 32 (65.3%) in arm B. No significant clinicopathological differences were observed at baseline between the two arms, except for tumors in arm B showing more TLS (50.0% vs. 12.5%, p=0.013). Median PFS (mPFS) with CT+/-ET was numerically shorter than mPFS with CDK4/6i+ET (11.2 vs. 19.9 months, HR: 1.41, 95%CI: 0.75-2.64, p=0.289). The median OS (mOS) for arm A was not estimable (NE) vs. 30.6 months in arm B (p=0.283). In arm A, median TILs levels were 3% (interquartile range [IQR]: 1-5%) and TLS, with/without germinal centers, were present in 2 cases (12.5%). These were also the only IF tumors in the arm, whereas the rest (87.5%) were ID. In arm B, 7 (25.0%) tumors were IF, 19 (87.5%) ID and 2 (7.1%) IE. Median TILs were 4.5% (IQR: 2-12.8%) and TLS were present in 50% cases. In arm A, ID tumors showed lower mPFS than IF (15.8 vs. 27.5 months), with concordant trend at the OS KM curve. In arm B there was no clear difference in PFS, but IF tumors did not reach mOS, differently from ID (28.7 months) and IE (28.1 months). High vs. low TILs levels were significantly associated with better PFS (p=0.003) and OS (p=0.005) in arm A. High levels of a TGFβ gene expression signature were significantly associated with better PFS (p=0.020) and OS (p=0.005) in arm A and PFS (p=0.03) in arm B; higher levels of a cytokine/chemokine signature were associatedwith better PFS (p=0.02) in arm A, and higher levels of a mastcells signature was associated with worse OS in both arms (p=0.02 and p=0.03). In arm B, higher levels of a macrophage (p < 0.001) and antigen presentation signatures (p=0.04) were associated with worse and better OS, respectively, whereas higher levels of an immune infiltration and a cytotoxic cells signature were associated with better PFS (p=0.03 both). TLS presence was numerically associated to longer mPFS (23.5 vs. 15.8 months) in arm A, with consistent OS KM curve’s trend, and longer mOS (44.5 vs. 28.1 months) in arm B. Conclusions: The KENDO trial further supports CDK4/6i+ET use in aggressive CT-naïve HR+/HER2- MBC. Biomarkers of immune activation such as IF tumors, higher TILs and presence of TLS pointed towards better survival outcomes. Genomic immunological features also showed prognostic effect, with differences according to treatment arm and/or the immune process or cell line tracked. Further research on larger cohorts is needed to confirm these preliminary findings. Citation Format: Francesco Schettini, Michela Palleschi, Francesca Mannozzi, Fara Brasó-Maristany, Lorenzo Cecconetto, Patricia Galván, Marita Mariotti, Alessia Ferrari, Emanuela Scarpi, Anna Miserocchi, Oriana Nanni, Esther Sanfeliu, Aleix Prat, Andrea Rocca, Ugo De Giorgi. Immunologic features and association with prognosis in hormone receptor-positive/HER2-negative (HR+/HER2-) metastatic breast cancer (MBC) treated with chemotherapy (CT) or CDK4/6-inhibitors (CDK4/6i) + endocrine therapy (ET) [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-14-06.

Abstract CT255: AdvanTIG-204: A phase 2, multicenter, randomized, 3-arm, open-label study investigating the preliminary efficacy and safety of ociperlimab (anti-TIGIT) + tislelizumab (anti-PD-1) + concurrent chemoradiotherapy (cCRT) in patients with untreated limited-stage small cell lung cancer (SCLC)

Abstract Background: Despite a high response rate to cCRT, patients with limited-stage SCLC generally experience recurrence of disease after a few months and survival remains poor. Immunotherapy has shown benefit in many tumor types, including SCLC. In preclinical and clinical studies of solid tumors, co-inhibition of T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibitor motif domains (TIGIT) and PD-1 enhanced antitumor activity of anti-PD-1. AdvanTIG-204 (NCT04952597) investigated the efficacy and safety of ociperlimab + tislelizumab + cCRT in patients with untreated limited-stage SCLC. Methods: Patients with limited-stage SCLC and no prior systemic therapy were randomized 1:1:1 to Arm A (ociperlimab [900 mg IV Q3W] + tislelizumab [200 mg IV Q3W] + cCRT for 4 cycles, then ociperlimab + tislelizumab), Arm B (tislelizumab + cCRT for 4 cycles, then tislelizumab), or Arm C (cCRT for 4 cycles). Study drugs (Arms A and B) were continued for up to 12 months or until progression, unacceptable toxicity, or withdrawal. Primary endpoint: investigator-assessed PFS per RECIST v1.1. Secondary analyses included additional efficacy and safety endpoints in the ITT population, and efficacy in patient subgroups by PD-L1 and TIGIT expression (both <1% vs ≥1%), using tumor area positivity (PD-L1) and immune cell scoring (TIGIT). No hypothesis testing was predefined (p-value for descriptive purposes only). Descriptive comparisons were conducted for Arm A vs C, B vs C, and A vs B. Results: As of July 26, 2023, 126 patients (median age, 61.5 years) were randomized to Arm A (n=41), Arm B (n=42), or Arm C (n=43). Median follow-up: ~18 months (all arms). There was a trend of improvement in median PFS in Arm A (12.6 months) and Arm B (13.2 months) vs Arm C (9.5 months); HR (95% CI): Arm A vs C, 0.84 (0.46-1.52; p=0.2793); Arm B vs C, 0.80 (0.45-1.44; p=0.2414). ORR was 85.4% (3 CR) in Arm A, 88.1% (4 CR) in Arm B, and 76.7% (1 CR) in Arm C. Median DoR was 10.1 months in Arm A, 11.5 months in Arm B, and 8.2 months in Arm C. Median OS was not reached in any arm. Analyses showed that PD-L1 or TIGIT expression did not correlate with efficacy, however, small subgroup size limits interpretability. All patients experienced ≥1 treatment-related adverse event (TRAE); rates of grade ≥3 TRAEs were 73.2%, 78.6% and, 65.1% in Arms A, B, and C, respectively. The most common TRAEs included anemia (80.5% in Arm A vs 83.3% in Arm B vs 81.4% in Arm C), nausea (80.5% vs 76.2% vs 65.1%), and WBC count decreased (78.0% vs 76.2% vs 62.8%). Rates of TRAEs leading to any treatment discontinuation were 26.8%, 21.4%, and 4.7% in Arms A, B, and C, respectively. One patient in each arm experienced a TRAE leading to death. Conclusion: In patients with untreated limited-stage SCLC, tislelizumab + cCRT yielded a trend of improvement in PFS and ORR vs cCRT; addition of ociperlimab did not show detectable improvement. The overall safety profile of the treatments was tolerable, manageable, and generally consistent with the known risks of ociperlimab, tislelizumab, and cCRT. Citation Format: Youling Gong, Qingsong Pang, Rong Yu, Zhengfei Zhu, Jiangqiong Huang, Yufeng Cheng, Diansheng Zhong, Hongbo Wu, Seung Soo Yoo, Tracy Dobbs, Zinan Bao, Yunxia Zuo, Boxian Wei, Pu Sun, You Lu. AdvanTIG-204: A phase 2, multicenter, randomized, 3-arm, open-label study investigating the preliminary efficacy and safety of ociperlimab (anti-TIGIT) + tislelizumab (anti-PD-1) + concurrent chemoradiotherapy (cCRT) in patients with untreated limited-stage small cell lung cancer (SCLC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT255.

Phase II randomized trial comparing metronomic anthracycline-containing chemotherapy versus standard schedule in untreated HER2 negative advanced breast cancer: activity and quality of life results of the GOIM 21003 trial

BackgroundOptimizing chemotherapy to achieve disease and symptoms control is a noteworthy purpose in advanced breast cancer (ABC). We reported the activity and quality of life of a phase II study, comparing metronomic regimen with standard schedule as first line chemotherapy for ABC. MethodsPatients with HER2 negative ABC were randomized to non-pegylated liposomal doxorubicin (NPLD, 60 mg/m2 every 3 weeks) and cyclophosphamide (CTX, 600 mg/m2 every 3 weeks) (Arm A) or NPLD (20 mg/m2 day, on day 1, 8 and 15 every 4 weeks) and metronomic daily oral CTX 50 mg (ARM B). Primary end-points were overall response rate (ORR) and quality of life, secondary progression-free survival (PFS), overall survival (OS) and toxicity. ResultsFrom August 2012 to December 2017, 121 patients were enrolled, 105 evaluable. Median follow-up was 21.3 months. Most patients had hormone receptor positive. ORR was 43 % in arm A and 50 % in arm B. Median PFS was 8.9 months in arm A and 6,4 months in arm B. There was no difference in OS. Total score was not clinically different between the two arms. Grade 4 neutropenia was observed in 12 patients and 16 patients respectively; alopecia G2 in 41 % (77 %) vs 14 (27 %) in arm A and in arm B respectively. One cardiac toxicity was observed (arm A). ConclusionsFirst line metronomic chemotherapy for HER2 negative ABC had similar clinical activity and quite better tolerability than standard schedule and could be considered a further treatment option when chemotherapy is indicated.

Abstract CT125: A phase 0/2 ‘trigger’ trial of pamiparib or olaparib plus radiotherapy in patients with newly-diagnosed or recurrent glioblastoma

Abstract Background: This Phase 0/2 clinical trial evaluates the pharmacokinetic (PK), pharmacodynamic (PD), and clinical response of newly-diagnosed and recurrent glioblastoma (GBM) patients to the PARP1/2 selective inhibitors, pamiparib and olaparib, in combination with radiotherapy. Materials/Methods: In this study, newly-diagnosed (Arm A) and recurrent GBM (Arm B) patients received 4 days of pamiparib (60 mg BID) prior to planned resection at 2-4 or 8-12 hours following the final dose. Arm C included recurrent GBM patients who received 4 days of olaparib (200 mg BID) prior to resection. In the Phase 0 component of the study total and unbound drug concentrations were measured using validated LC-MS/MS methods. A PK ‘trigger’, defined as unbound drug > 5-fold biochemical IC50 in Gd-nonenhancing tumor, determined eligibility for Phase 2. PARP inhibition was assessed via ex vivo tumor tissue radiation and quantification of PAR levels compared to non-irradiated control. When demonstrating a PK response, newly-diagnosed, MGMT-unmethylated GBM or recurrent GBM patients were eligible for Phase 2 dosing of pamiparib (Arms A and B) or olaparib (Arm C) with concurrent RT followed by maintenance pamiparib or olaparib. Results: A total of 41 patients (Arm A, n=16; Arm B, n=19; Arm C, n=6) were enrolled in the Phase 0 component of the study. In Arms A and B, mean unbound concentrations of pamiparib in Gd-nonenhancing tumor were 167.3 nM and 104.3 nM respectively, and in Arm C the mean unbound concentration of olaparib was 5.2 nM. All patients in the pamiparib arms (n=35) but only 1 of 6 patients in the olaparib Arm C exceeded the PK threshold. Radiation-induced PAR expression was 2.44-fold in untreated control vs 1.16 in Arm A (p<0.05), 0.82 in Arm B (p<0.01) and 1.11 in Arm C patients. In Arm A, 7 of 11 MGMT-unmethylated GBM patients advanced to Phase 2. Two patients were ineligible due to clinical status, 1 patient was ineligible per physician decision, and 1 patient declined to participate. In Arm B, 11 of 19 patients advanced to Phase 2. Eight patients were ineligible due to clinical status. At a mean follow-up of 5.8 months, median progression-free survival (PFS) was 5.8, 6.0, and 3.8 months for Arms A (n=7), B (n=11), and C (n=1), respectively. Grade 3+ toxicities related to pamiparib occurred in 4 patients, with 2 adverse events resulted in treatment discontinuation. No grade 3+ toxicities were documented in the olaparib arm. Conclusions: Pamiparib achieved pharmacologically-relevant concentrations in Gd-nonenhancing GBM tissue and suppressed induction of PAR levels ex vivo post-radiation. The majority of newly-diagnosed patients with MGMT-unmethylated GBM and recurrent GBM patients advanced to therapeutic dosing in this trial, and pamiparib was generally well-tolerated in these patients. Citation Format: Nader Sanai, Yu-Wei Chang, Jun Jiang, Jennifer Molloy, Chelsea Pennington-Krygier, Jocelyn Harmon, Amy Hong, John Wanebo, William Kennedy, Michael Garcia, Igor Barani, Wonsuk Yoo, Artak Tovmasyan, An-Chi Tien, Jing Li, Shwetal Mehta. A phase 0/2 ‘trigger’ trial of pamiparib or olaparib plus radiotherapy in patients with newly-diagnosed or recurrent glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT125.