Short term safety of coronavirus disease 2019 vaccines in patients with solid tumors receiving systemic therapy

BACKGROUND

There are currently three coronavirus disease 2019 (COVID-19) vaccines approved by the United States Food and Drug Administration to prevent coronavirus infection. However, robust data are unavailable on the adverse events of the vaccines in patients with solid tumor malignancies undergoing systemic therapies.

AIM

To evaluate the safety of COVID-19 vaccines in patients with solid tumors undergoing systemic therapies.

METHODS

The study included patients with solid tumors treated in an academic tertiary care center who received COVID-19 vaccination between January 1, 2021 and August 15, 2021, while undergoing systemic therapy. Electronic medical records were accessed to collect information on patient characteristics, systemic therapies, type of vaccine received, and adverse effects associated with the vaccine administration. Adverse events (AEs) were graded according to Common Terminology Criteria for Adverse Events, version 5.0.

RESULTS

The analysis included 210 patients; the median age was 70 years, and 51% of patients were female. The most common chemotherapy, immunotherapy, and targeted therapy administered were taxane-based regimens 14.2% (30/210), anti-programmed death 1 (PD-1) agents 22.8% (48/210), and antiangiogenic agents 7.1% (15/210), respectively. The most common cancers were gastrointestinal 43.8% (92/210), thoracic 30.4% (64/210), and genitourinary 17.6% (37/210). Patients received the following vaccines: 2 doses of BNT162b2 by Pfizer 52% (110/210), 2 doses of mRNA-1273 by Moderna 42% (89/210), and 1 dose of JNJ-78436735 by Johnson & Johnson 5% (11/210). At least 1 AE attributable to the vaccine was observed in 37 patients 17.6% (37/210). The total number of AEs attributable to vaccines was 62: Fifty-three grade 1 and nine grade 2. Most adverse events occurred after the second dose 59.7% (37/62). The most frequent grade 1 AEs included fatigue 17% (9/53), fever 15% (8/53), injection site reaction 13.2% (7/53), and chills 9.4% (5/53). The most frequent grade 2 AEs were fatigue 33.3% (3/9) and generalized weakness 22.2% (2/9). Therapy was delayed by 2 wk because of the AEs possibly related to vaccine administration in 3 patients 1.4% (3/210).

CONCLUSION

The present study demonstrates that the adverse events associated with COVID-19 vaccination are infrequent, mild, and rarely delay treatment in patients with solid tumors receiving systemic therapies.

MEK-inhibitor (inh) and hydroxychloroquine (HCQ) in KRAS-mutated advanced pancreatic ductal adenocarcinoma (PDAC)

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Background: Therapeutic inhibition of constitutive signaling mediated by mutated KRAS in PDAC remains a challenge except for modest success reported with KRAS G12C inhibition. A combinatorial strategy utilizing simultaneous MEK and autophagy inhibition holds therapeutic promise based on mechanism of action and preclinical data. We described characteristics and outcomes of patients (pts) treated with MEK-inh and HCQ at our institution. Methods: Ten KRAS-mutated advanced PDAC pts were treated with trametinib-HCQ (n = 9) or cobimetinib-HCQ (n = 1) off label due to lack of standard treatment options or toxicity concerns with cytotoxic systemic therapy. Trametinib dose was 2 mg once daily orally, Cobimetinib dose was 20 mg BID orally for 3/4 weeks cycles. HCQ was started at 200 mg BID and up-titrated weekly to 600 mg BID. Description of baseline and treatment (tx) characteristics, safety and efficacy is provided. Results: Median age at diagnosis was 61.3 years, and 7 pts were female. The number of prior lines of tx were 0/1/2/3/4 in 3/2/1/2/2 pts, respectively. KRAS mutations were: G12R/G12D/G12V/Q61H in 6/2/1/1 pts. Median overall survival was 6.6 months (m) in all pts, and 6.6/1.7 m in KRAS G12R/other KRAS (p = 0.31). Median progression-free survival was 5.7/6.2/1.5 m in all/ KRAS G12R/other KRAS (p = 0.16). Among 8 pts with evaluable response, 1 (12%) had partial response ( KRAS G12R) and 4 (50%) stable disease (3/4 KRAS G12R) as best response with disease control rate of 63%/80%/33% in total/ KRAS G12R/other KRAS (p = 0.29). Toxicity data are summarized in table 1. Conclusions: MEK-inh-HCQ demonstrated modest efficacy and manageable toxicities among KRAS G12R PDAC pts. Unlike G12D and G12V mutations in the KRAS gene, G12R is defective of conductive interactions for both PI3Ka and NF1. This ultimately results in a weakened signal being shunted through MAPK cascade and provides a unique opportunity where MEK inh can ablate signaling without the alternate pathways and WT-RAS isoforms compensating. Furthermore, as activation of PI3Ka is known to suppress autophagy, its lack of activation by KRAS G12R further sensitizes cells to HCQ. The combination therapy MEK-inh-HCQ is therefore mechanistically-rationale and warrants the further investigation of KRAS G12R as an actionable biomarker.[Table: see text]

Clinical course and outcome of patients developing capecitabine-induced non-neutropenic enterocolitis (NNEC): An institutional analysis

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Background: Non-neutropenic enterocolitis (NNEC), a potentially fatal toxicity of capecitabine (CAPE), is under-reported in the literature. An institutional review was performed to determine the incidence, clinical course, and outcome of patients developing CAPE-induced NNEC. Methods: After the institutional review board approval, a database search identified patients requiring inpatient care for CAPE-induced diarrhea over a period of 6 years (between 01/2015 and 12/2020). Among the patients requiring hospital admission, patients with radiologic features of enterocolitis were included in the analysis. Data on patient characteristics, imaging study results, clinical course, and outcomes were gathered by electronic chart review. Results: Among the 789 patients treated with CAPE, 25 patients (3%) developed grade 3 or higher diarrhea requiring hospital admission, and 13 out of these 25 patients (1.6 % of patients treated with CAPE) had evidence of enterocolitis on CT scan: ileitis in 7/13 (54%), colitis in 1/13 (8%), and both in 5/13 (38%) patients. The median age of the patient cohort was 64 years (range, 31-81), 8/13 (62%) were female, and all patients were Caucasian. CAPE was administered for the following indications: breast cancer in 6 patients, colorectal cancer in 4 patients, cholangiocarcinoma in 2 patients, and neuroendocrine tumor in 1 patient. ECOG performance status at the time of CAPE initiation was 0 in 7 patients and 1 in 6 patients. Most patients (7/13, 54%) received single-agent CAPE, and the majority (10/13, 77%) developed diarrhea with the first cycle after a median of 21 days (range, 10-50). Patients were hospitalized after a median of 27 days (range, 13-51), and the median hospital stay was 12 days (range, 4-25). None of the 13 patients demonstrated neutropenia at the time of hospital admission. The associated adverse effects at the time of admission included grade 3 abdominal pain in 8 (62%) patients, grade 3 nausea in 7 (54%) patients, and grade 3 vomiting in 3 (23%) patients. Hypokalemia and oral mucositis were present at admission in 6 (46%) and 2 (15%) patients, respectively. Stool studies performed in 11 (85%) patients ruled out infection. Testing for dihydropyrimidine dehydrogenase deficiency performed in 4 (31%) patients was negative. All patients were treated with supportive measures, and 2 (15%) patients required total parenteral nutrition. All but 1 patient recovered fully; 1 patient died due to a condition unrelated to CAPE. Intravenous infusional 5-fluorouracil (5-FU) administration in 3 patients after the recovery was tolerated well. Conclusions: CAPE-induced NNEC is uncommon and generally occurs after the first cycle of therapy. Most patients developing CAPE-induced NNEC recover fully with appropriate supportive measures. Infusional 5-FU-based regimens appear to be safe in this patient group.

A prospective observational study to determine the feasibility of tumor response assessment by circulating tumor DNA (ctDNA) in patients with locally advanced rectal cancer (LARC) undergoing total neoadjuvant therapy (TNT)

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Background: Total neoadjuvant therapy (TNT) followed by total mesorectal excision (TME) is one of the standard treatment options for patients with locally advanced rectal cancer (LARC). A commonly employed TNT protocol consists of 8 biweekly cycles of oxaliplatin-based chemotherapy (CT) followed by radiation concurrent with fluoropyrimidine-based chemotherapy (CRT) for about 6 weeks. During the TNT, patients undergo tumor response assessments periodically with standard modalities (SM) consisting of pelvic magnetic resonance imaging (MRI) and proctoscopic/endoscopic examination. The objective of the current protocol is to evaluate the feasibility of tumor response assessment by ctDNA in patients with LARC undergoing TNT. The present feasibility study is designed to collect preliminary data to evaluate if a subsequent larger validation study is justified. If ctDNA-based response assessment is validated, ctDNA can potentially replace at least some components of the SM (for example, MRI) as tumor response assessment by SM is often time-consuming, expensive, and poses logistical challenges. Methods: Patients with LARC undergoing TNT will be enrolled. After obtaining informed consent, venous blood samples will be obtained for ctDNA level measurements at the following time points: baseline (within 1 week before the CT begins), after 4 cycles of CT within +/- 5 days of the MRI study, after 8 cycles of CT within +/- 5 days of the MRI study, and 1 to 14 days before TME. ctDNA levels will be measured by a commercially available ctDNA assay (Signatera by Natera), and ctDNA response is defined as >90% drop in the ctDNA level after treatment compared to the baseline level. Tumor response will be evaluated after 4 and 8 cycles of CT by SM. Primary endpoint: correlation between the response rate (RR) assessed by ctDNA and by SM after 4 cycles of CT. Secondary endpoints: 1) correlation between the RR assessed by ctDNA and by SM after 8 cycles of CT, and 2) correlation between the ctDNA defined RR and the complete pathological response (pCR) rate. The trial will enroll 30 patients. To evaluate the primary endpoint, differences in ctDNA levels between the baseline and 4-cycles post-CT will be computed. The differences will then be expressed as a proportion of each patient’s baseline level, D. This relative change, D, will be compared between the responder and non-responder groups using a two-sample Welch’s t-test. Similar methods will be applied for the secondary endpoints. All analyses will use the nominal type I error level of 0.05 and two-sided tests. Clinical trial information: NCT04670588.

Survival outcome and treatment response of patients with young-onset locally advanced rectal cancer (YO-LARC) receiving total neoadjuvant therapy (TNT)

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Background: Despite an alarming rise in incidence, data on survival outcome and treatment response of young-onset (age < 50 years) locally advanced rectal cancer (YO-LARC) patients receiving total neoadjuvant therapy (TNT) are sparse. We retrospectively compared the outcome between YO-LARC and later-onset (aged 50 years or older) LARC (LO-LARC) patients treated with TNT. Methods: After the institutional review board approval, electronic medical records of the LARC (T3/T4 or node-positive) patients treated with TNT at a tertiary care cancer center between January 1, 2015, and June 30, 2020, were reviewed for data collection. TNT consisted of systemic chemotherapy with oxaliplatin-based regimens for 16 weeks followed by long-course radiation with concurrent capecitabine or 5-fluorouracil (CRT). Patients receiving only preoperative CRT were excluded. Most patients underwent surgical resection following the TNT. Non-operative management was offered to patients if TNT resulted in clinical complete response (cCR). The following comparisons between the YO-LARC and the LO-LARC patients were performed: patient characteristics, pathological complete response (pCR) rate, combined pCR + cCR rate, disease-free survival (DFS), and overall survival (OS). Results: Of 72 patients included in the analysis, 44(61%) were male, 49 (68%) were Caucasian, and 62 (86%) had clinical stage III disease. The study included 26 (36%) patients with YO-LARC (median age, 43 years) and 46 (64%) patients with LO-LARC (median age, 64 years). The comparison of patient characteristics that included gender, clinical stage, baseline carcinoembryonic antigen level, the distance of the tumor from the anal verge, presence of high-risk features, and histologic grade did not differ significantly between the groups. There were no statistically significant differences in pCR and combined pCR+cCR rates (p = 0.16) between the groups: YO-LARC, 12 % (3/26) and 15 % (4/26), respectively; LO-LARC, 22% (10/46) and 30% (14/46), respectively. Either group did not reach median DFS and OS after a median follow-up of 38 months for survivors. The estimated 5-year OS rates in patients with YO-LARC and LO-LARC were 86 % (95% confidence interval [CI], 69% to 100%) and 84% (95% CI, 68% to 100%), respectively (p = 0.92). The estimated 3-year DFS rates in patients with YO-LARC and LO-LARC were 67 % (95% CI, 50% to 89%) and 83% (95% CI, 72% to 95%), respectively (p = 0.19). Conclusions: The current retrospective analysis did not demonstrate significant differences in the pCR rates, combined pCR +cCR rates, DFS, or OS between the YO-LARC and LO-LARC patients treated with TNT.

TAS-102: A resurrected novel Fluoropyrimidine with expanding role in the treatment of gastrointestinal malignancies

TAS-102 is an orally administered fixed-dose formulation consisting of trifluorothymidine (TFT), a fluoropyrimidine antimetabolite, and tipiracil (TPI), an inhibitor of thymidine phosphorylase (TP) that prevents rapid degradation of TFT and ensures its bioavailability. The novelty of TAS-102 lies in its antitumor activity against 5-fluorouracil (5-FU) resistant tumors, demonstrated both in the in vitro models and xenografts. The cytotoxic activity of TFT relies primarily on extensive incorporation of the TFT metabolite into the cellular DNA inducing DNA dysfunction and cell death. In contrast, 5-fluorouracil (5-FU) interferes with DNA biosynthesis by inhibiting thymidylate synthase(TS), which partly explains the absence of cross-resistance between TAS-102 and 5-FU. TAS-102 is currently approved in the third-line setting for patients with metastatic colorectal and gastric cancer based on phase III randomized clinical trial data confirming an overall survival benefit with TAS-102. The preliminary data from recently reported studies suggest a potential expanding role of TAS-102 in a variety of gastrointestinal (GI) cancers. The current article presents an overview of the pharmacology, clinical development of TAS-102, and its emerging role in the treatment of GI cancers. In addition, we discussed the rationale underlying the ongoing clinical trials investigating various combinations of TAS-102 with other anticancer agents, including targeted therapies, in a wide range of GI tumors.

Abstract 654: Application of comprehensive genomic profiling (CGP) to predict therapeutic response to immune checkpoint inhibitors (ICI)

Introduction : Immune check point inhibitors(ICIs) are widely used to treat various solid tumors, but there is a paucity of biomarkers that reliably predict response to such therapy. We sought to identify somatic alterations (SAs) that can predict response to ICI. Further, we investigated the effect of these SAs on clinical outcome. Methods: We retrospectively reviewed medical records of all patients (pts) that received ICI at our institution (2012-2017) and had CGP performed on pre-treatment biopsies. DNA was extracted from formalin fixed paraffin embedded clinical specimens and CGP was performed on hybrid-capture, adaptor ligation based libraries to a mean coverage depth of &gt;600 unique reads utilizing the Foundation Medicine platform (315 gene panel). Twenty-four SAs, occurring in at least 5% of the pts were correlated with response using the Wilcoxon-Mann-Whitney test and p-values were adjusted for multiple testing using Benjamini-Hochberg's false-discovery rate (FDR) method. Cox proportional hazards regression was used to investigate the effect of baseline covariates on progression-free survival (PFS); The effect of SAs was analyzed using the exact log rank test. The effect of response on progression and death was investigated using a 4-state model with “ICI therapy”, “response”, “progression”, and “death” as possible states. Results: Among the 76 pts that met criteria, 71 (lung-25, urothelial-6, esophageal-6, gynecologic-6, renal-5, sarcoma-5, melanoma-4, colorectal-4, prostate-3, head and neck-3, other-4) had an evaluable response and were included in the analyses. Median age was 62 years, 6 (8.5%) pts received ICI as first line therapy, while 65 (91.5%) pts received a median of 1 line of therapy prior to ICI; median of 5 doses of ICI therapy were administered. Complete Response (CR), Partial Response (PR), Stable Disease (SD), and Progressive Disease (PD) were noted in 3 (4.2%), 11 (15.5%), 10 (14.1%) and 47 (66.2%) pts respectively. SAs in RBM10 (p = 0.0024), PIK3CA (p = 0.0027), ARID1A (p = 0.0039), and SMARCA4 (p = 0.0047) correlated with response in a statistically significant fashion (adjusted p value = 0.028). PFS and overall survival (OS) of the entire cohort was 3.7 and 11.4 months respectively. Pts with SAs in RBM10 (p = 0.0011), ARID1A (p = 0.0102), and PIK3CA (p = 0.0013) demonstrated a statistically significant improvement in PFS (median not met, not met, and 9.3 months, respectively). Response to ICI significantly reduced the hazard of progression (HR=0.11, p=0.0006), but not the hazard of non-relapse mortality (NRM) (HR=0.41, p=0.53). Conclusion: CGP was able to identify SAs predictive of response to ICI and improved PFS. The significant reduction in the hazard of progression with response to ICI emphasizes the predictive value of the identified biomarkers. The validity and putative mechanistic relevance of these predictive SAs need further elucidation.

Citation Format: Ravi K Narra, Arun K Singavi, Jonathan Thompson, Smitha Menon, James Thomas Thomas, Carolyn Oxencis, Mathew Riese, Paul Ritch, Deepak Kilari, Aniko Szabo, Ben George. Application of comprehensive genomic profiling (CGP) to predict therapeutic response to immune checkpoint inhibitors (ICI) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 654.