Citations

AbstractImmune checkpoint inhibitors (ICIs), as a novel class of anticancer therapy, can be more efficacious and less toxic than chemotherapy, but their clinical success is confined to certain tumor types. Elucidating their targets, mechanisms and scope of action, and potential synergism with chemotherapy and/or targeted therapies are critical to widen their clinical indications. Treatment response to an ICI targeting programmed death‐1 (anti‐PD‐1) is sought to be understood here by conducting a preplanned correlative analysis of a phase II clinical trial in patients with small bowel adenocarcinoma (SBA). The cytolytic capacity of circulating immune cells in cancer patients using a novel ex vivo cytotoxicity assay is evaluated, and the utility of circulating biomarkers is investigated to predict and monitor the treatment effect of anti‐PD‐1. Baseline expression of Bim and NKG7 and upregulation of CX3CR1 in circulating T cells are associated with the clinical benefit of anti‐PD‐1 in patients with SBA. Overall, these findings suggest that the frequency and cytolytic capacity of circulating, effector immune cells may differentiate clinical response to ICIs, providing a strong rationale to support immune monitoring using patient peripheral blood.

AbstractPurposeRural populations are disproportionately affected by the COVID‐19 pandemic. We characterized urban‐rural disparities in patient portal messaging utilization for COVID‐19, and, of those who used the portal during its early stage in the Midwest.MethodsWe collected over 1 million portal messages generated by midwestern Mayo Clinic patients from February to August 2020. We analyzed patient‐generated messages (PGMs) on COVID‐19 by urban‐rural locality and incorporated patients’ sociodemographic factors into the analysis.FindingsThe urban‐rural ratio of portal users, message senders, and COVID‐19 message senders was 1.18, 1.31, and 1.79, indicating greater use among urban patients. The urban‐rural ratio (1.69) of PGMs on COVID‐19 was higher than that (1.43) of general PGMs. The urban‐rural ratios of messaging were 1.72‐1.85 for COVID‐19‐related care and 1.43‐1.66 for other health care issues on COVID‐19. Compared with urban patients, rural patients sent fewer messages for COVID‐19 diagnosis and treatment but more messages for other reasons related to COVID‐19‐related health care (eg, isolation and anxiety). The frequent senders of COVID‐19‐related messages among rural patients were 40+ years old, women, married, and White.ConclusionsIn this Midwest health system, rural patients were less likely to use patient online services during a pandemic and their reasons for its use differ from urban patients. Results suggest opportunities for increasing equity in rural patient engagement in patient portals (in particular, minority populations) for COVID‐19. Public health intervention strategies could target reasons why rural patients might seek health care in a pandemic, such as social isolation and anxiety.

Abstract Background: I-SPY 2 is a multicenter, phase 2 trial using response-adaptive randomization within molecular subtypes defined by receptor status and MammaPrint (MP) risk to evaluate novel agents as neoadjuvant therapy for women with high-risk breast cancer. Tucatinib is a potent HER2 (ErbB2) tyrosine kinase inhibitor, selective for HER2 vs. epidermal growth factor receptor (EGFR) and is active vs. brain metastases. Safety and efficacy of tucatinib combined with paclitaxel, pertuzumab, and trastuzumab are unknown and were tested in a planned 10 patient (pt) safety run-in of the I-SPY 2 trial. Methods: Women with tumors ≥ 2.5cm were eligible for screening. Only pts with tumors that were HER2+ by FISH were eligible for this treatment. Treatment included tucatinib (max dose 300 mg) BID for 12 weeks with weekly paclitaxel 80 mg/m2 and trastuzumab (2 mg/kg weekly following loading), and pertuzumab (420 mg every 3 weeks following loading), followed by doxorubicin/cyclophosphamide (AC) every 2 weeks x 4. The control arm was weekly paclitaxel and trastuzumab with pertuzumab for 12 weeks followed by AC every 2 weeks x 4. All pts undergo serial MR imaging and response at 3 & 12 weeks is combined with real time pCR data to estimate, and continuously update, the predicted pCR rate for each trial arm. The goal of the trial is to identify/graduate regimens with ≥85.% Bayesian predictive probability of success (i.e. demonstrating superiority to control) in a future 300-patient phase 3 neoadjuvant trial with a pCR endpoint. This run-in arm was conducted to determine safety of combining tucatinib with paclitaxel/trastuzumab/pertuzumab, monitoring special adverse events of interest including LFT elevations and gastrointestinal toxicities.Methods: The I-SPY 2 methods have been previously published. Results: 20 pts were evaluable in tucatinib treatment arm. The control arm included 329 historical controls enrolled since April 2010. The initial tucatinib dose was 300 mg BID. After enrollment of the first 8 pts, there were 3 pts with grade 3 LFT elevations, 2 pts with grade 2/3 diarrhea, 1 pt with grade 2 neutropenia, and 1 pt with grade 3 nausea. After this safety review, the tucatinib dose was lowered to 250 mg BID. Among 5 additional pts enrolled, 3 developed grade 2/3 LFT abnormalities. The protocol was then modified to tucatinib 150 mg BID days 1-28 and then 250 mg BID days 29-84; 7 pts were treated. Safety data were reviewed after 20 pts were enrolled; the arm was then suspended due to similar LFT elevations regardless of tucatinib dose reduction or schedule. 7 of 20 pts (35%) had reversible Grade 3 or higher ALT/AST elevation (Table). No pt met criteria for Hy’s Law. In terms of efficacy, 12 of 14 evaluable pts had > 80% reduction of tumor volume by 12 weeks, measured by MRI assessment of functional tumor volume (FTV). Conclusion: The goal of the run-in arm was to determine the safety of adding tucatinib to the combination of paclitaxel/trastuzumab/pertuzumab. The addition of tucatinib resulted in unacceptable but reversible LFT elevations despite tucatinib dose reduction. Tucatinib containing therapy resulted in >80% decline in tumor volume at 12 weeks in 86% of pts. Tucatinib showed a high level of activity when combined with paclitaxel/trastuzumab/pertuzumab, but the combination is not feasible. Table: Number of pts with grade 2, 3, and 4 LFT elevations by treatment schedule (highest grade per patient per event, ALT or Treatment scheduleGrade 2 LFT elevationGrade 3 LFT elevationGrade 4 LFT elevationTucatinib 300 mg BID030Tucatinib 250 mg BID210Tucatinib 150 mg BID days 1-28 followed by 250 mg BID days 29 to 84112 Citation Format: David A Potter, Erin Roesch, Christina Yau, Ruixiao Lu, Denise Wolf, Susan Samson, Debra Stafford, Kathy S Albain, Claudine Isaacs, Meghana Trivedi, Douglas Yee, Judy Boughey, Alexandra Thomas, A. Jo Chien, Nola Hylton, Wen Li, Angela DeMichele, Jane Perlmutter, W. Fraser Symmans, Dawn L Hershman, Michelle Melisko, Laura J van 't Veer, Amy Wilson, Smita M Asare, Donald A Berry, Richard Schwab, Hope S Rugo, Laura J Esserman. Evaluation of Tucatinib + (Paclitaxel + Pertuzumab + Trastuzumab) followed by AC in high-risk HER2 positive (HER2+) stage II/III breast cancer: Results from the I-SPY 2 TRIAL [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr PD8-07.

TPS194 Background: Despite a growing number of treatment options for first line mCRPC, approximately 40% of patients (pts) have radiographic progression within the first year. Androgen receptor (AR) signaling inhibition increases genomic instability with double-strand DNA breaks & co-inhibition of AR & PARP induces synthetic lethality in multiple preclinical models. Homologous recombination repair (HRR) gene aberrations do not appear to be necessary for this synergy as demonstrated in a ph 2 clinical trial of abiraterone & olaparib where this combination improved radiographic progression-free survival (rPFS) in HRR-wild-type pts compared with abiraterone alone. A ph 1b trial has since shown that enzalutamide plus rucaparib has acceptable safety profile & no significant drug-drug interactions (S-DDI). Methods: CASPAR/A031902 (NCT04455750) is a ph 3 study in which 984 pts will be randomized 1:1 to enzalutamide plus rucaparib or placebo. HRR gene aberration is not required for enrollment. All pts will undergo next-generation targeted-exome sequencing from archival tumor tissue (new biopsy only required if no archival tissue available). Treatment will be continued until disease progression & crossover is not allowed. Key eligibility criteria are age ≥ 18 years, ECOG PS 0-2, biopsy-proven prostate adenocarcinoma, progressive (PSA or radiographic) disease per Prostate Cancer Working Group 3 guidelines, measurable or nonmeasurable disease per RECIST 1.1, no prior treatment for mCRPC (prior docetaxel, abiraterone, darolutamide, or apalutamide in non-mCRPC setting is allowed), no significant uncontrolled comorbidity, & no medications with S-DDI with enzalutamide/rucaparib. Hierarchical co-primary endpoints are rPFS & overall survival (OS). The OS analysis will be undertaken as a primary endpoint if the rPFS endpoint is met. For a one-sided logrank test with a type 1 error rate equal to 0.025, the study has 90% power to detect a hazard ratio (HR) of 0.71 in rPFS (median rPFS of 15 & 21 months in control & combination arms, respectively) & 80% power to detect an HR of 0.80 in OS (median OS of 32 & 40 months, respectively). Key secondary endpoints are rPFS & OS in pts with vs without pathogenic BRCA1, BRCA2, or PALB2 alterations; & differences in adverse events & quality of life (QOL) outcomes between the treatment arms. QOL assessments include Functional Assessment of Cancer Therapy–Prostate (FACT-P), Brief Pain Inventory Short Form (BPI-SF) & EQ-5D-5L. A key correlative endpoint is the sensitivity of ctDNA-based testing for alterations in HRR genes. Enrollment to CASPAR began in July 2021 & the study is available for participation to all US-NCTN sites with a projected enrollment of 3 years. Support: U10CA180821, U10CA180882, U24CA196171; U10CA180888; Clovis Oncology; http://acknowledgments.alliancefound.org Clinical trial information: NCT04455750.

Gliomas are the most common malignant primary brain tumor in adults. Despite advances in multimodality therapy, incorporating surgery, radiotherapy, systemic therapy, tumor treating fields and supportive care, patient outcomes remain poor, especially in glioblastoma where median survival has remained static at around 15 months, for decades. Low-grade gliomas typically harbor isocitrate dehydrogenase (IDH) mutations, grow more slowly and confer a better prognosis than glioblastoma. However, nearly all gliomas eventually recur and progress in a way similar to glioblastoma. One of the novel therapies being developed in this area are poly(ADP-Ribose) polymerase (PARP) inhibitors. PARP inhibitors belong to a class of drugs that target DNA damage repair pathways. This leads to synthetic lethality of cancer cells with coexisting homologous recombination deficiency. PARP inhibitors may also potentiate the cytotoxic effects of radiotherapy and chemotherapy, and prime the tumor microenvironment for immunotherapy. In this review, we examine the rationale and clinical evidence for PARP inhibitors in glioma and suggest therapeutic opportunities.

Large segmental osseous defects heal poorly. Recombinant, human bone morphogenetic protein-2 (rhBMP-2) is used clinically to promote bone healing, but it is applied at very high doses that cause adverse side effects and raise costs while providing only incremental benefit. We describe a previously unexplored, alternative approach to bone regeneration using chemically modified messenger RNA (cmRNA). An optimized cmRNA encoding BMP-2 was delivered to critical-sized femoral osteotomies in rats. The cmRNA remained orthotopically localized and generated BMP locally for several days. Defects healed at doses ≥25 μg of BMP-2 cmRNA. By 4 weeks, all animals treated with 50 μg of BMP-2 cmRNA had bridged bone defects without forming the massive callus seen with rhBMP-2. Moreover, such defects recovered normal mechanical strength quicker and initiated bone remodeling faster. cmRNA regenerated bone via endochondral ossification, whereas rhBMP-2 drove intramembranous osteogenesis; cmRNA provides an innovative, safe, and highly translatable technology for bone healing.

Abstract Background Validation of the 2016 RANO MRI scorecard for leptomeningeal metastasis failed for multiple reasons. Accordingly, this joint EORTC Brain Tumor Group and RANO effort sought to prospectively validate a revised MRI scorecard for response assessment in leptomeningeal metastasis. Methods Coded paired cerebrospinal MRI of 20 patients with leptomeningeal metastases from solid cancers at baseline and follow-up after treatment and instructions for assessment were provided via the EORTC imaging platform. The Kappa coefficient was used to evaluate the interobserver pairwise agreement. Results Thirty-five raters participated, including 9 neuroradiologists, 17 neurologists, 4 radiation oncologists, 3 neurosurgeons, and 2 medical oncologists. Among single leptomeningeal metastases-related imaging findings at baseline, the best median concordance was noted for hydrocephalus (Kappa = 0.63), and the worst median concordance for spinal linear enhancing disease (Kappa = 0.46). The median concordance of raters for the overall response assessment was moderate (Kappa = 0.44). Notably, the interobserver agreement for the presence of parenchymal brain metastases at baseline was fair (Kappa = 0.29) and virtually absent for their response to treatment. 394 of 700 ratings (20 patients x 35 raters, 56%) were fully completed. In 308 of 394 fully completed ratings (78%), the overall response assessment perfectly matched the summary interpretation of the single ratings as proposed in the scorecard instructions. Conclusion This study confirms the principle utility of the new scorecard, but also indicates the need for training of MRI assessment with a dedicated reviewer panel in clinical trials. Electronic case report forms with “blocking options” may be required to enforce completeness and quality of scoring.