Physician awareness of immune-related adverse events from checkpoint inhibitors

6571

Background: Immune checkpoint inhibitors (ICIs) have been one of the most significant developments in Oncology over the last decade. Despite being very effective for certain patient subsets, they have a unique side effect profile different from conventional chemotherapy that can manifest as immune-related adverse events (IRAEs). With increasing ICI use, clinicians will increasingly encounter these adverse events and thus, adequate knowledge on recognition and management of IRAEs is very important. Methods: To assess physician knowledge on IRAEs of ICIs, an online survey was administered to resident physicians in internal medicine (IM), emergency medicine (EM) and family medicine (FM) as well as to faculty physicians in IM, and FM at 3 tertiary care hospitals in Indiana. Results: We sent the survey to 413 physicians out of which 155 responded with a response rate of 38%. Out of 155 physicians, 110 were residents and 45 were faculty (27 hospitalists and 17 primary care physicians). Pembrolizumab was identified as a checkpoint inhibitor correctly by 79% of physicians, nivolumab by 64% and ipilimumab by 55%. Twenty-five percent of physicians incorrectly believed infliximab and adalimumab were ICIs. Most physicians (93%) were able to identify the gastrointestinal tract as an IRAE site whereas only 57% and 67% were able to identify cardiovascular and renal systems as an IRAE site, respectively. Fifty-nine percent of physicians believed steroids negatively affect efficacy of ICIs and should be used with caution to treat IRAEs. Sixty-five percent of physicians incorrectly thought endocrinopathies due to IRAEs are usually reversible. Most physicians (79%) believed IRAEs most commonly manifest in the first 6 months of treatment. Forty-five percent of FM residents considered antibiotics as the mainstay of treatment in ICI associated immune mediated colitis; this was significantly different from EM (15%) and IM (8%) residents(p = 0.0004). When comparing between residency programs, on a scale of 0-100, IM residents felt significantly more comfortable identifying IRAEs secondary to ICIs (27.1±24.2) when compared to EM (12.2±12.7) and FM residents (9.4±13.8; p = 0.0009). There was no significant difference among IM (19.8±20.1), EM (11.9±13.6), and FM residents (11.6±18.9; p = 0.11) when comparing how comfortable they were in treating IRAEs. When asked what the best way would be to learn about IRAEs, 36% chose printed material and algorithms, 30% picked online teaching module and 30% chose one time in-person lecture from an Oncologist. Conclusions: Resident and faculty physicians in multiple specialties are not comfortable in the management and treatment of IRAEs due to ICIs. Given that most of these physicians are usually the first point of contact with patients, physician education on identification and treatment of IRAEs is needed. Early detection of these toxicities is critical for their resolution.

Consolidation nivolumab plus ipilimumab or nivolumab alone following concurrent chemoradiation for patients with unresectable stage III non-small cell lung cancer: BTCRC LUN 16-081

8509

Background: The PACIFIC trial demonstrated that a year of consolidation PD-(L)1 inhibition following concurrent chemoradiation (CRT) for unresectable stage III NSCLC improves overall survival (OS). The optimal duration of consolidation IO therapy in this setting is undefined. Studies in metastatic NSCLC demonstrate that combination PD-(L)1/CTLA-4 inhibition improves OS over chemotherapy alone. This trial evaluated the use of combination Nivolumab (N) plus Ipilimumab (IPI) or N alone for up to 6 months in unresectable stage III NSCLC after concurrent CRT. Methods: This is a randomized phase II, multicenter trial of 105 pts with unresectable stage IIIA/IIIB NSCLC. All pts received concurrent CRT and were then enrolled and randomized 1:1 to receive N 480mg IV q4wks (Arm A) for up to 24 weeks or N 3mg/kg IV q2 wks + IPI 1mg/kg IV q6 wks (Arm B) for up to 24 weeks. The primary endpoint is 18-month PFS compared to historical controls of CRT alone for arm A (30%) and CRT followed by Durva for arm B (44%). Secondary endpoints include OS and toxicity. Results: From 9/2017 to 4/2021, 105 pts were enrolled and randomized, 54 to N alone (A) and 51 to N + IPI (B). The baseline characteristics for arm A/B: median age (65/63), male (44.4%/56.9%), stage IIIA (55.6%/56.9%), stage IIIB (44.4%/43.1%), non-squamous (57.4%/54.9%), and squamous (42.6%/45.1%). The percentage of pts completing the full treatment was 70.4% on A and 56.9% on B (p = 0.15). Median f/u was 24.5 and 24.1 months on A and B, respectively. The 18-month PFS was 62.3% on A (p < 0.1) and 67% on B (p < 0.1), and median PFS was 25.8 months and 25.4 months, respectively. Median OS was not reached on either arm, but the 18- and 24-month OS estimates were 82.1% and 76.6% for A and 85.5% and 82.8% for B, respectively. Treatment-related adverse events (trAE) on arm A/B were 72.2%/80.4%, and grade ≥3 trAEs on arm A/B were 38.9%/52.9%. There was 1 grade 5 event on each arm (COVID19-A, Cardiac Arrest-B). The number of pts with grade ≥2 pneumonitis were 12 (22.2%) on A and 15 (29.4%) on B, with 5 (9.3%) and 8 (15.7%) grade ≥3 events, respectively. The most common ( > 10%) non-pneumonitis trAEs on A were fatigue (31.5%), rash (16.7%), dyspnea (14.8%), and hypothyroidism (13%), and on B were fatigue (31.4%), diarrhea (19.6%), dyspnea (19.6%), pruritus (17.7%), hypothyroidism (15.7%), rash (15.7%), arthralgia (11.8%), and nausea (11.8%). Conclusions: Following concurrent CRT for unresectable stage III NSCLC, both N and N + IPI demonstrated improved 18-month PFS compared with historical controls despite a shortened interval (6 months) of treatment. OS data are still maturing but 18- and 24-month OS estimates compare favorably to prior consolidation trials. Toxicity for N alone was similar to prior single-agent trials, and the combination of N + IPI resulted in a higher incidence of trAE’s, although consistent with prior reports. Clinical trial information: NCT03285321.

Analysis of circulating tumor DNA in the phase 2 BTCRC LUN 16-081 trial of consolidation nivolumab with or without ipilimumab after chemoradiation in stage III non–small cell lung cancer

8534

Background: The current standard of care for patients with inoperable stage III non-small cell lung cancer (NSCLC) includes chemoradiation (CRT) followed by up to 1 year of checkpoint inhibitor (CPI) therapy. However, many patients are not able to complete 1 year of treatment and the optimal duration of consolidation therapy remains unknown. Identifying minimal residual disease (MRD) via detection of circulating tumor DNA (ctDNA) may help inform the optimal duration of treatment. Here we report the results of a preplanned correlative study evaluating the association between detectable ctDNA and survival outcomes from the BTCRC LUN 16-081 phase 2 trial of consolidation nivolumab or nivolumab plus ipilimumab following CRT in patients with unresectable Stage III NSCLC (NCT03285321). Methods: Following CRT, patients with unresectable stage IIIA/B NSCLC were randomized 1:1 to receive nivolumab 480 mg IV Q4weeks for up to 6 cycles or nivolumab 240 mg IV Q2weeks plus ipilimumab 1 mg/kg IV Q6weeks for up to 4 cycles. Plasma samples for ctDNA analysis were collected after completion of CRT, prior to C2D1 of CPI, and at the end of treatment or withdrawal from the study. Tumor genotyping and ctDNA analysis were performed using CAPP-Seq with a panel targeting 260 genes recurrently mutated in NSCLC. Patient-specific tumor variants were identified using tumor tissue or baseline plasma and matched leukocyte DNA samples. Tumor variants were then monitored in plasma samples using a tumor mutation-informed bioinformatic strategy. Results: Thirty-nine patients received either nivolumab (n = 25; cycles: median = 6, range 1-6), or nivolumab plus ipilimumab (n = 14; cycles; median = 2, range = 1-6). Patients with detectable ctDNA MRD after completion of CRT demonstrated significantly inferior progression free survival (PFS) than patients who were MRD-negative (12-month 29% vs 76%, 24-month 29% vs 68%, P = 0.003), prior to C2D1 of CPI (12-month 0% vs 85%, 24-month 0% vs 72%, P < 0.0001) and at the end of CPI (12-month 14% vs 90%, 24-month 14% vs 79%, P < 0.0001). Patients with undetectable ctDNA MRD at the end of CPI (median cycles = 5.5; range 1-6) demonstrated 24-month overall survival of 91%. Additionally, patients with decreasing or undetectable ctDNA levels after one cycle of CPI had improved outcomes compared to patients with increasing ctDNA levels (24-month PFS 73% vs 0%, P < 0.0001). Progression of disease occurred within 10.8 months of starting CPI in all patients with increasing ctDNA levels at C2D1. Conclusions: Detectable ctDNA before, during, and after consolidation CPI is strongly associated with inferior survival outcomes. Furthermore, less than 12 months of CPI consolidation can result in MRD negativity and high rates of long term PFS. Clinical trial information: NCT03285321.

Ezabenlimab (BI 754091), an anti-PD-1 antibody, in combination with BI 836880, a VEGF/Ang2-blocking nanobody, in patients (pts) with advanced colorectal cancer (CRC)

98

Background: Anti-PD-1 antibodies may have synergistic effects with other immunomodulatory or targeted agents. This open-label, Phase II platform trial is investigating ezabenlimab, an anti-PD-1 antibody, combined with other agents. Module C of the platform is assessing ezabenlimab plus BI 836880, a humanized bispecific nanobody targeting VEGF/Ang2. Pts are being enrolled into 5 advanced solid tumor cohorts: gastric/gastroesophageal adenocarcinoma; solid tumors (except non-squamous NSCLC or melanoma) with secondary resistance to anti-PD-(L)1 treatment (progression after at least SD for ≥4 months); solid tumors with primary resistance to anti-PD-(L)1 treatment; microsatellite stable (MSS) CRC; mismatch repair-proficient/MSS endometrial carcinoma. Here, we report data from the CRC cohort which has completed recruitment. Methods: Pts with locally advanced, unresectable or metastatic, MSS CRC were enrolled. Patients had received ≥1 line of prior systemic therapy for metastatic disease but were anti-PD-(L)-1 therapy-naïve. Prior anti-angiogenic therapy was permitted. Pts received BI 836880 720 mg plus ezabenlimab 240 mg iv q3w for 1 year or until disease progression, consent withdrawal or undue toxicity. Primary endpoint: investigator-assessed OR (CR or PR per RECIST v1.1). Secondary endpoints: duration of response, disease control, and PFS; safety is also being assessed. Results: 30 pts have been treated: 57% male; median age 61.5 years. All pts had received prior chemotherapy; most pts (23 [77%]) had received prior bevacizumab. At data cut-off (Sep 2021), median duration (range) of treatment was 115.5 (28–295) days; 6 pts remain on treatment. 1 (3%) pt (who had not received prior bevacizumab) achieved a confirmed PR; 16 (53%) pts had SD. Median duration (range) of SD was 128.5 (42–242) days. 29/17/2 (97/57/7%) pts had an AE (any/G3/G4). The most frequent AEs (any/G3) were nausea (40/10%), fatigue (30/3%), peripheral edema (30/0%), vomiting (27/7%), and hypertension (27/17%). There were two G4 AEs (hypertension; platelet count decreased) and no G5 AEs. 24/10/2 (80/33/7%) pts had a drug-related AE (any/G3/G4); most commonly (any/G3) nausea (33/7%), fatigue (27/3%) and hypertension (27/17%). 3 (10%) pts had an infusion-related reaction (G1, n = 1; G2, n = 2). 2 (7%) pts had an AE leading to discontinuation (G3 bile duct stone and G2 peripheral edema). Immune-related AEs were reported in 6 (20%) pts and serious AEs occurred in 13 (43%) pts. Conclusions: BI 836880 plus ezabenlimab had a manageable safety profile in pts with advanced MSS CRC; however, anti-tumor activity was limited in these pts, the majority of whom had received prior bevacizumab. Clinical trial information: NCT03697304.

A randomized phase II trial of adjuvant pembrolizumab versus observation following curative resection for stage I non-small cell lung cancer (NSCLC) with primary tumors between 1-4 cm: Big Ten Cancer Research Consortium BTCRC-LUN18-153

TPS8583

Background: There are approximately 35,000 cases of stage I lung cancer in the United States each year. While these patients have better 5-year overall survival (OS) rates than their counterparts with locally advanced and metastatic disease, there is still considerable room for improvement. Based on a recent publication validating the 8th edition of the TNM classification, the 5-year OS for node-negative pathologically-staged NSCLC between 1-4cm ranges from 73-86%, and recurrence rates for resected stage I NSCLC can range from 18-38%. Previous studies looking at adjuvant chemotherapy in this setting have shown no benefit for stage IA tumors, and the current standard of care is observation alone. Checkpoint blockade with PD-1/PD-L1 inhibitors has shown considerable activity in NSCLC including in metastatic disease, as consolidation in stage III disease after chemoradiation, and in studies evaluating neoadjuvant immunotherapy. Given this activity and their favorable safety profile, we designed a study of adjuvant PD-1 inhibition following resection in stage I NSCLC. Methods: This study is a randomized phase II multicenter trial of adjuvant Pembrolizumab versus observation alone following complete resection of stage I NSCLC with tumors between 1-4cm. The trial will enroll 368 patients randomized 1:1 to either Pembrolizumab 400mg IV every 6 weeks for up to 9 cycles or observation alone with scheduled CT scans and routine clinical follow-up. Stratification factors include PD-L1 ≥50% vs. < 50% and tumor size of 1-2cm vs. > 2-4cm. The lead site is Indiana University, and the trial will be conducted through the Big Ten Cancer Research Consortium. The primary endpoint is disease free survival (DFS), and secondary endpoints include OS, DFS at 1-, 2-, and 3-year time points, and toxicity. The trial opened to accrual at the lead site in May 2020, and there are currently 6 patients enrolled. Clinical trial information: NCT04317534.

Trial in progress: A phase 1b study of sotorasib, a specific and irreversible KRASG12C inhibitor, as monotherapy in non-small cell lung cancer (NSCLC) with brain metastasis and in combination with other anticancer therapies in advanced solid tumors (CodeBreaK 101)

TPS2669

Background: Kirsten rat sarcoma viral oncogene homolog ( KRAS) p.G12C mutation is an oncogenic driver mutation in several solid tumors. Sotorasib is a specific, irreversible, small molecule inhibitor of KRASG12C that has demonstrated durable clinical benefit in NSCLC, with mild and manageable toxicities. The combination of sotorasib with other anticancer therapies may enhance antitumor efficacy. This master protocol is designed to evaluate safety, tolerability, pharmacokinetics (PK), and efficacy of multiple sotorasib combinations in patients (pts) with KRASp.G12C mutated solid tumors. Herein, we overview 1 monotherapy and 11 combination cohorts. Methods: This is a phase 1b, open-label study evaluating sotorasib alone and in combination regimens (Table) in pts with advanced KRAS p.G12C mutated solid tumors. Dose exploration will evaluate the safety and tolerability of sotorasib alone and in combination regimens; dose expansion will then verify the safety and tolerability profile of sotorasib regimens and assess antitumor efficacy. Key eligibility criteria include locally-advanced or metastatic solid tumor with KRAS p.G12C mutation identified through molecular testing in pts who have received ≥1 lines of prior systemic therapy. Primary endpoints include dose-limiting toxicities and treatment-emergent or treatment-related adverse events. Secondary endpoints include PK profile of combination regimens and efficacy (eg, objective response, disease control, duration of response, progression-free survival, and duration of stable disease assessed per RECIST 1.1). Enrollment began in December 2019 and is ongoing. Clinical trial information: NCT04185883. [Table: see text]

A phase II trial of chemotherapy plus pembrolizumab in patients with advanced NSCLC previously treated with a PD-1 or PD-L1 inhibitor: Big Ten Cancer Research Consortium BTCRC-LUN15-029

9073

Background: Chemoimmunotherapy with a platinum doublet plus a checkpoint inhibitor (CPI) is a standard of care for pts with advanced NSCLC. While some pts experience prolonged responses to initial CPI therapy, the majority of pts will eventually experience PD. It is unknown if continuing CPI treatment beyond progression has any advantages in this setting. We report the results of a phase 2 trial of chemotherapy plus pembrolizumab in pts with advanced NSCLC previously treated with a PD-1 or PD-L1 inhibitor. Methods: Pts experiencing PD after clinical benefit to CPI (PFS > 3 months) were enrolled. Pts received pembrolizumab 200 mg q3wks plus next-line chemotherapy (gemcitabine 1000 mg/m2 IV D1 and D8 q3wks, or docetaxel 60-75 mg/m2 IV D1 q3wks, or pemetrexed 500 mg/m2 IV D1 q3wks [non-squamous histology only]). The primary endpoint was PFS by RECIST 1.1. Key secondary endpoints included ORR, OS, and toxicity. The null hypothesis was median 3-month PFS with pembrolizumab plus next-line chemotherapy and the alternative hypothesis was median 6-month PFS with pembrolizumab plus chemotherapy. Results: 35 pts were enrolled. Median follow-up was 18.1 months and median age 63 (44-80). 51.4% male and 48.6% female. 82.9% were current or former smokers. Histology included 74.3% with adenocarcinoma, 20% with squamous cell carcinoma, 5.7% with NSCLC NOS. Treatment regimens included pembrolizumab/docetaxel (40%), pembrolizumab/gemcitabine (45.7%), or pembrolizumab/pemetrexed (14.3%). Median number of cycles of pembrolizumab was 6 (1-31). Median PFS using RECIST 1.1 and irRECIST was 5.2 months (95% CI 3.6-11.2, p < 0.05) and 6.9 months (95% CI 3.8-12), respectively. Median OS was 26.8 months (95% CI 13.4-30.9). Best response using RECIST 1.1 was PR (23.5%) and SD (53%). 45.7% of pts experienced G3 or higher treatment-related AEs (TRAEs). Most common TRAEs were fatigue (60%), anemia (51.4%), and nausea (42.9%). There were no treatment related deaths. Conclusions: Pembrolizumab plus next-line chemotherapy in pts with advanced NSCLC who experienced PD after clinical benefit to CPI was associated with prolonged PFS compared with historical controls of single agent chemotherapy. Further investigations into which pts would benefit from continued CPI treatment after progression is warranted. Clinical trial information: NCT03083808.

Consolidation nivolumab/ipilimumab versus nivolumab following concurrent chemoradiation in patients with unresectable stage III NSCLC: A planned interim safety analysis from the BTCRC LUN 16-081 trial

9010

Background: Consolidation PD-1/PD-L1 inhibition after chemoradiation (CRT) for unresectable stage III NSCLC improves overall survival. In stage IV NSCLC, the combination of nivolumab/ipilimumab improved overall survival compared to chemotherapy in patients with PD-L1 > 1% and performed favorably in patients with PD-L1 < 1%. The safety of consolidation nivolumab/ipilimumab after CRT has not been previously assessed. Methods: In this randomized, multi-center, phase II study, a total of 105 planned pts with unresectable stage IIIA/IIIB NSCLC will receive chemoradiation, then randomize 1:1 to either nivolumab 480mg IV q4 wks (Arm A) or nivolumab 3mg/kg IV q2 wks + ipilimumab 1mg/kg IV q6 wks (Arm B), for up to 24 wks. In this planned interim analysis, the safety of the first 50 patients, with 25 patients treated on each arm, is assessed. Results: From 9/2017 to 6/2019, the first 50 patients were accrued and analyzed for this planned safety analysis. Baseline characteristics for Arm A/B: median age 64/62, stage IIIA 17/16, stage IIIB 8/9, non-squamous 14/13, squamous 11/12. The median number of cycles completed in Arm A was 6 (range 1-6, cycle length q4 wks) and in Arm B was 4 (range 1-4, cycle length q6 wks). The rate of treatment-related adverse events leading to discontinuation of therapy was 16% in Arm A and 40% in Arm B. The percentage of patients with any > grade 3 adverse event (AE) was 32% in Arm A and 44% in Arm B. With respect to immune-related AE (irAEs), the percentage of patients with any ≥grade 2 was 44% in Arm A and 60% in Arm B; any ≥ grade 3 irAEs was 16% in Arm A and 32% in Arm B. The incidence of > grade 2 pneumonitis was 16% in Arm A and 36% in Arm B. The percentage of patients with > grade 3 pneumonitis was 4% in Arm A and 20% in Arm B. No treatment-related deaths were reported on either arm. Conclusions: In the post chemoradiation setting, the incidence of > grade 3 toxicity was greater in the consolidative nivolumab/ipilimumab arm, which resulted in a higher rate of treatment discontinuation than nivolumab alone. The Data and Safety Monitoring Board recommended continued enrollment without modification to the trial and the study currently remains open to accrual (66 of 105 patients have been enrolled as of 1/17/2020). Clinical trial information: NCT03285321.

The association between immune-related adverse events and efficacy outcomes with consolidation pembrolizumab after chemoradiation in patients with stage III NSCLC: an analysis from HCRN LUN 14-179

9032

Background: Consolidation checkpoint inhibitor therapy (CPI) for up to 1 year following chemoradiation (CRT) is a current standard of care for pts with inoperable stage III NSCLC. However, some pts are not able to complete 1 year of CPI due to immune-related adverse events (irAES). In multiple retrospective studies, pts with stage IV NSCLC treated with CPI who experience irAEs generally receive fewer cycles of CPI without a significant detrimental effect on efficacy. The association between irAEs and outcomes with consolidation CPI after CRT has never been reported. Here we report the association between irAEs and efficacy outcomes from the HCRN LUN 14-179, a single-arm phase II trial of consolidation pembrolizumab following concurrent CRT in pts with unresectable stage III NSCLC. Methods: After completion of CRT eligible pts with stage III NSCLC without PD received pembrolizumab 200 mg IV q 3 wks for up to 1 yr. Demographics, disease characteristics, and number of cycles of pembrolizumab received were reported in pts who had any grade irAEs (except pneumonitis which included grade >2 only) [Group A] and those without irAEs (except grade 1 pneumonitis) [Group B]. Chi-square test (or Fisher's Exact test) were used for comparisons for categorical variables and Wilcoxon test for continuous variables. The Kaplan-Meier method was used to analyze time to metastatic disease (TMDD), PFS, and OS. A log-rank test was used to compare groups. Results: 92 eligible pts for efficacy analysis were enrolled from March 2015 to November 2016. 4 yr OS estimate for all pts is 46.2%. Any grade irAEs (except grade I pneumonitis) (n = 37 pts) included pneumonitis (18.5%), colitis (3.3%), increased creatinine (5.4%), elevated transaminases (3.3%), hyperthyroidism (7.6%), hypothyroidism (13.0%). Grade ≥ 2 irAEs (n = 32 pts) included pneumonitis (18.5%), hypothyroidism (10.8%), and colitis (3.3%). Group A/B: male (21/38), female (16/17), current or former smoker (35/52), stage IIIA (20/35), stage IIIB (17/20), non-squamous (21/30), squamous (16/25). Median number of pembrolizumab cycles received in Group A/B pts were 9 vs 15 (p = 0.0942) respectively. 4 yr efficacy endpoints in Groups A/B were TMDD 35.3% vs 41.3% (p = 0.83), PFS 27.8% vs 28.7% (p = 0.97), OS 43.5% vs 47.9% (p = 0.99), respectively. Conclusions: Despite receiving fewer cycles of consolidation pembrolizumab, pts who experienced any grade irAEs (excluding grade 1 pneumonitis) did not have significantly reduced efficacy outcomes. Clinical trial information: NCT02343952.

Trial in progress: A phase Ib study of AMG 510, a specific and irreversible KRASG12C inhibitor, in combination with other anticancer therapies in patients with advanced solid tumors harboring KRAS p.G12C mutation (CodeBreak 101)

TPS3661

Background: Kirsten rat sarcoma viral oncogene homolog (KRAS) p.G12C mutation has been identified as a driver oncogenic mutation in several solid tumors (eg, non-small cell lung cancer [NSCLC], colorectal cancer [CRC]). Development of therapies targeting KRASG12C has been unsuccessful. AMG 510 is a specific and irreversible small molecule inhibitor of KRASG12C. A first-in-human clinical trial of AMG 510 monotherapy in patients with KRAS p.G12C mutant solid tumors is currently ongoing. AMG 510 in combination with additional anticancer therapies may lead to enhanced antitumor efficacy. This study is a master protocol designed to evaluate multiple investigational regimens of AMG 510 in patients with KRAS p.G12C mutant solid tumors. Here, we present two combination cohorts of AMG 510 with a mitogen-activated protein kinase kinase (MEK) inhibitor and an investigational anti-programmed cell death protein-1 (PD-1) therapy, respectively. Additional combination cohorts will be presented at the meeting. Methods: This is a phase 1b, open-label study evaluating AMG 510 in combination with a MEK inhibitor or an investigational anti-PD-1 therapy in pts with KRAS p.G12C mutant solid tumors. The dose exploration phase (part 1; n=20) will evaluate the safety and tolerability of AMG 510 in combination with the MEK inhibitor or anti-PD-1 therapy; this will be followed by a dose expansion phase (part 2; n=40) to verify the safety and tolerability profile of AMG 510 combination therapies and assess antitumor efficacy. Key eligibility criteria include locally-advanced or metastatic malignancy with KRAS p.G12C mutation identified through molecular testing and at least one or multiple lines of prior systemic therapy (eg, ≥2 for advanced/metastatic colorectal cancer). Primary endpoints include dose-limiting toxicities, treatment-emergent or -related adverse events. Secondary endpoints include pharmacokinetic parameters of combination regimens, disease control rate, duration of response, progression-free survival, and duration of stable disease (measured by computed tomography or magnetic resonance imaging and assessed per RECIST 1.1). The study began enrolling pts in December 2019 and is ongoing. For more information, please contact Amgen Medical Information: medinfo@amgen.com . Clinical trial information: NCT04185883 .

CodeBreak 100: Activity of AMG 510, a novel small molecule inhibitor of KRASG12C, in patients with advanced colorectal cancer

4018

Background: Kirsten rat sarcoma viral oncogene homolog (KRAS) p.G12C mutation is associated with poor prognosis in colorectal cancer (CRC). AMG 510 is a first-in-class small molecule that specifically and irreversibly inhibits KRASG12C by locking it in the inactive guanosine diphosphate-bound state. In a previous interim analysis of the phase 1, first-in-human trial of AMG 510, we observed a favorable safety profile and preliminary antitumor activity in patients (pts) with advanced solid tumors harboring KRAS p.G12C. Here, we present updated data in pts with CRC. Methods: Key inclusion criteria were KRAS p.G12C mutation identified through molecular testing, measurable disease, and progression on standard therapy. Primary endpoint was safety. Secondary endpoints were objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), as assessed per RECIST 1.1, and overall survival (OS). Oral daily doses of 180, 360, 720, and 960mg were tested in the dose escalation phase, and 960mg dose was selected for the expansion phase. Results: As of Jan 8, 2020, 42 pts with CRC (21 female [50%], median age: 57.5 years [range: 33–82]) were enrolled and dosed (25 on 960mg). All pts received prior systemic therapies; 19 pts (45.2%) received > 3 prior lines. Median follow-up was 7.9 months (mos) (range: 4.2–15.9). 13 pts (31.0%) died, and 8 pts (19.0%) remained on treatment (tx). 22 (52.4%) and 8 (19.0%) pts had remained on tx for more than 3 and 6 months, respectively. Progressive disease was the most common reason for tx discontinuation. 20 pts (47.6%) had tx-related adverse events (TRAEs): 18 (42.9%) had grade 2 or lower TRAEs; 2 (4.8%) had grade 3 TRAEs, which were diarrhea (2.4%) and anemia (2.4%). There were no dose-limiting toxicities, fatal TRAEs, or TRAEs leading to tx discontinuation. Overall, ORR and DCR were 7.1% (3/42) and 76.2% (32/42), respectively. At 960mg, ORR and DCR were 12.0% (3/25) and 80.0% (20/25). 3 pts with PR had duration of response of 1.5, 4.2, and 4.3 months, respectively, and their responses were still ongoing at data cutoff. In all pts treated with all doses, median duration of stable disease was 4.2 mos (range: 2.5[+]–11.0). PFS/OS will be reported. Conclusions: In pts with heavily pretreated KRAS p.G12C mutant CRC, AMG 510 monotherapy was well tolerated, with the majority of pts achieving disease control. Study is ongoing. Clinical trial information: NCT03600883 .

Implementation and uptake of an interactive virtual online tumor board across NCI-Cancer Centers

272

Background: Expert knowledge is often shared among academic oncologists at tumor boards (TBs) at National Cancer Institute Designated Cancer Centers (NCI-CCs), but not documented or made accessible to community oncologists. Using an oncologist-only question and answer (Q&A) website, we sought to disseminate expert insights from TBs at NCI-CCs to provide educational benefit to the oncology community. Methods: A process was designed with faculty at 11 NCI-CCs to document and share discussions from TBs focused on areas of clinical complexity and practice variation on theMednet.org, an interactive Q&A website of over 8,700 US oncologists. One faculty member from each TB was selected as a site leader. She or he distilled discussions about patient management from the TB into a question that addressed the clinical situation being discussed. After the question was posted, faculty at the participating NCI-CCs were asked to answer the question on theMednet. Answers were peer reviewed, indexed, stored and disseminated via email newsletters to registered oncologists. Community engagement was measured by Q&A page views, upvotes of Q&A, and poll participation. Results: A total of 15 Breast, Thoracic, and Gastrointestinal programs from 11 NCI-CCs participated. Between 12/2016 and 5/2019, faculty highlighted 146 questions from their TBs. Q&A were viewed 43,291 times by 3,585 oncologists including 2,264 community oncologists. One hundred and eighty-four answers are posted by 56 academic physicians and peer reviewed by 76 academic physicians. One hundred and eighty-five publications were cited. Community oncologists upvoted Q&A 808 times and voted in 45 polls related to the questions 1,667 times. Viewership of NCI-CC Q&A increased by 419% over time. Q&A were repeatedly searched and viewed, with 90% of all TB Q&A viewed every month. Conclusions: Via the online Q&A theMednet platform, NCI-CC providers effectively made expert knowledge easily accessible to community oncologists across the US. Timely access to evidence based recommendations from expert faculty can inform future practice choices in the community.

[Table: see text]

Interim safety analysis of consolidation nivolumab and ipilimumab versus nivolumab alone following concurrent chemoradiation for unresectable stage IIIA/IIIB NSCLC: Big Ten Cancer Research Consortium LUN 16-081

8535

Background: Consolidation PD-1 inhibition after chemoradiation (chemoRT) for unresectable stage IIIA/IIIB NSCLC improves overall survival. The efficacy and safety of combining a CTLA-4 inhibitor with a PD-1 inhibitor in this setting are unknown but may further improve efficacy in this patient population. Methods: In this randomized, multi-center, phase II study, 105 pts with unresectable stage IIIA/IIIB NSCLC will receive chemoRT, then randomize 1:1 to either nivolumab 480mg IV q4 wks (nivo) or nivolumab 3mg/kg IV q2 wks + ipilimumab 1mg/kg IV q6 wks (nivo/ipi), for up to 24 wks. In this interim analysis, we assess the safety of the first 20 patients treated. Results: From 9/2017 to 11/2018, 20 patients were accrued. Characteristics of those treated on the nivo arm (n = 10) were: median age 62 years, stage IIIA/B 7/3; non-squamous/squamous 7/3; and the nivo/ipi arm (n = 10): median age 61 years; stage IIIA/B 6/4; non-squamous/squamous 7/3. Most toxicities were grade 1 or 2 and the most frequently noted grade 2 AEs included fatigue (25%), pneumonia (25%), extremity pain (20%). Adverse events reported in the Nivo only arm included 81 total events with only four grade 3 events and a single grade 4 thromboembolic event. The Nivo/Ipi arm reported 101 total AEs, with only 3 grade 3 events and a single grade 4 toxicity (amylase elevation). With respect to immune-related adverse events (irAEs), in the nivo arm there were two cases of grade 2 pneumonitis and no grade 3/ 4 events. In the nivo/ipi arm, there was one grade 2 pneumonitis, three grade 3 irAEs (pneumonitis, colitis, pancreatitis), and one asympomatic grade 4 amylase elevation. No treatment-related deaths were observed in either arm. Conclusions: There were no unexpected safety signals in the first 20 patients treated on BIG10CRC LUN 16-081. The incidence of grade 3 or higher irAEs was higher in the nivo/ipi arm, as expected, but this was manageable with the use of established guidelines. The study currently remains open to accrual (32 of 105 have been randomized as of 2/8/19). Clinical trial information: NCT03285321.

Impact of smoke-free ordinance strength on smoking prevalence and lung cancer incidence

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Background: Smoke-free ordinances (SFO) have been shown to decrease the prevalence of cardiovascular and pulmonary disease, but there is limited data on the impact of such policies on lung cancer incidence. We investigated the relationship between strength of county-level SFO with smoking prevalence and lung cancer incidence in Indiana. Methods: Following IRB approval, we queried the Indiana State Cancer Registry and Indiana Tobacco Prevention and Cessation Commission’s policy database between 1995 and 2016. County-level characteristics included population, income, poverty, education, race/ethnicity, sex, and rurality. Lung cancer diagnosis and stage were also collected. Using generalized estimating equations (GEE) with robust standard errors and accounting for the clustering effect at county level, we performed multivariable analyses of smoking prevalence and age-adjusted lung cancer rates with respect to the strength of smoke-free ordinances at the county level over time. Results: Indiana consists of 92 counties, 24 of which had SFO by 2011. In 2012, Indiana enacted a law mandating at least a moderate state-wide SFO. From 1995 to 2016, 110,935 Indiana residents were diagnosed with lung cancer. Indiana also had an average age-adjusted yearly lung cancer incidence of 76.8 per 100,000 population and average yearly smoking prevalence of 25% during this time. Smoking prevalence was 1.2% (95% CI [-1.88, -0.52]) lower in counties with comprehensive or moderate SFO compared with those with weak or no SFO. Counties that had comprehensive or moderate SFO had an 8.36 (95% CI [-11.45, -5.27]) decrease in new lung cancer diagnosis per 100,000 population per year compared with counties that had weak or no SFO. Conclusions: Stronger municipal smoke-free air ordinances are associated with decreased smoking prevalence and fewer new lung cancer cases. Strengthening smoke-free ordinances is paramount to decreasing lung cancer incidence.

A phase II trial of consolidation nivolumab or nivolumab plus ipilimumab following concurrent chemoradiation in unresectable stage III NSCLC: BTCRC LUN16-081

TPS179

Background: Unresectable stage III NSCLC demonstrates poor 5-yr OS outcomes. The current standard of care for fit patients in this setting is concurrent chemoradiation. Previous studies evaluating the addition of induction or consolidation chemotherapy, EGFR-targeted agents, ant-angiogenic agents, and higher doses of radiation have failed to definitively improve OS over chemoradiation alone. Recently, a trial of consolidation PD-L1 inhibition demonstrated improved PFS over chemoradiation alone, and a second trial of consolidation PD-1 inhibition is awaiting data maturation. This may herald a change to the standard of care in this setting. The addition of CTLA-4 inhibition to anti-PD-1 monoclonal antibodies has shown improved OS in melanoma and has demonstrated encouraging early phase data in stage IV NSCLC. Therefore, we initiated a trial evaluating the addition of a CTLA-4 inhibitor to PD-1 inhibition for consolidation treatment of unresectable stage III NSCLC. Methods: This is a multi-center, randomized, phase II study of nivolumab or the combination of nivolumab and ipilimumab as consolidation therapy following concurrent chemoradiation in unresectable stage III NSCLC. Patients will receive concurrent chemoradiation with one of three standard chemotherapy backbones (Cis-Etop, Cis-Pem, or Carbo-Pac), and repeat imaging will be done 4-8 weeks following completion of therapy. Patients without progressive disease will be randomized 1:1 to receive either niv 480mg IV every 4 weeks or the combination of niv 3mg/kg IV every 2 weeks and ipi 1mg/kg IV every 6 weeks for up to 6 months. The trial will enroll a total of 108 patients with 54 in each arm. The two arms are non-comparator arms and will be compared with historical controls. The primary endpoint is the improvement of PFS at 18 months, and key secondary endpoints include OS and the toxicity of consolidation niv and niv/ipi. Exploratory endpoints will look at the correlation between multiple clinical, radiographic, and laboratory parameters and outcomes, as well as the association of these parameters with the development of pneumonitis. This trial opened to accrual in September 2017. Clinical trial information: NCT03285321.

Potential risk factors of pneumonitis associated with consolidation pembrolizumab after chemoradiation in unresectable NSCLC patients

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Background: We have previously shown that consolidation pembrolizumab after chemoradiation is safe in a 93 patient-clinical trial of unresectable stage III NSCLC patients (Durm, ASCO 2016). However 15 patients (16%) developed grade ≥2 pneumonitis. There is limited data on risk factors for developing pneumonitis in this population. We conducted a retrospective review of these patients to identify potential clinical, biologic, radiographic and radiation treatment related risk factors for developing pneumonitis. Methods: We evaluated ECOG PS, age, gender, smoking status, stage, histology, chemo regimen, consolidation chemotherapy, TILs, PDL-1 status, PFTs, PET SUVs, grade of pre-existing ILD, COPD and Radiation dosimetry plans. Logistic regression and fisher’s-exact test were used for the odds ratio and p-values. Results: See Table. [1] [1] Age, histology, stage, chemo, PFTs, SUVs and PDL1 were not significant [2] n = sample size p = pneumonitis [3] Moderate/severe COPD was not seen in any patients with pneumonitis despite 94% of participants being smokers. Conclusions: This preliminary report highlights the utility of a multi-disciplinary approach to develop risk-stratification models for pneumonitis in an at-risk patient population. However larger prospective studies are needed to validate their meaningful use in the clinical setting.[Table: see text]

Safety and feasibility of consolidation pembrolizumab following concurrent chemoradiation for unresectable stage III non-small cell lung cancer: Hoosier Cancer Research Network LUN14-179

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Background: The standard of care for unresectable stage III NSCLC is concurrent chemorad. Following treatment, the risk of radiation pneumonitis is greatest at 1-3 mo. Pneumonitis risk increases with consolidation chemotherapy. A previous trial by our group (Hanna et al, JCO 2008) of consolidation docetaxel showed 80.8% completed 3 planned cycles of chemo with a grade 3-5 pneumonitis rate of 9.6% and 1 death. PD-1 inhibitors are also associated with an increased risk of pneumonitis in the metastatic setting. We conducted a phase II trial of consolidation pembro initiated 1-2 mo after concurrent chemorad, a period during which pts are at high risk of developing pneumonitis. Methods: Pts with stage III NSCLC who completed chemorad with either carbo/paclitaxel, cis/etop, or cis/pemetrexed plus 59-66.6 Gy of radiation and had no PD received pembro 200mg IV q3wk for up to 1 yr. Primary endpoint is time to metastatic disease. The objective of the study is to evaluate both safety and efficacy, and here we report preliminary safety and feasibility results. Evaluable pts for this analysis had ≥3 mo of f/u or went off study due to PD, toxicity, or death < 3 mos after initiation of pembro. Results: 93 pts enrolled. Median age 67 (range 46-84), 59 (63.4%) were male. 87 (93.5%) were former or current smokers. 68 (73.1%) received carbo/pac, 24 (25.8%) received cis/etop, and 1 received cis/pemetrexed. SqCC (n = 41), non-SqCC (n = 43), NSCLC NOS (n = 8), mixed (n = 1). IIIA (n = 56), IIIB (n = 37). At the time of analysis, 83 of 93 pts were evaluable. 66 of 83 (79.5%) received ≥ 3 mo of pembro. 17 (20.5%) pts developed any grade pneumonitis with 14 of 17 occurring in the first 12 wks (median 9 wks). Only 3 (3.6%) pts developed grade 3-5 pneumonitis related to pembro. There was 1 pneumonitis-related death and a second death from respiratory failure possibly related to pembro. Conclusions: This early report indicates that most patients can safely receive consolidation pembro within 1-2 mo of completing chemorad. The incidence of serious pneumonitis during the first 3 mo of treatment appears low. Updated safety data on all 93 pts will be presented at the ASCO meeting. Clinical trial information: NCT02343952.