Regorafenib in Patients With Solid Tumors With BRAF Alterations: Results From the Targeted Agent and Profiling Utilization Registry (TAPUR) Study

PURPOSE

Targeted Agent and Profiling Utilization Registry is a phase II basket trial evaluating the antitumor activity of commercially available targeted agents in patients with advanced cancer with genomic alterations known to be drug targets. Results of a cohort of patients with solid tumors with BRAF alterations treated with regorafenib are reported.

METHODS

Eligible patients had measurable disease (RECIST v.1.1), Eastern Cooperative Oncology Group performance status 0-1, adequate organ function, and no standard treatment options. The primary end point was disease control (DC), defined as investigator assessment of patients with complete or partial response (PR) or stable disease of at least 16-weeks duration (SD16+). Low accruing histology-specific cohorts with BRAF alterations treated with regorafenib were collapsed into a single histology-pooled cohort for this analysis. The results were evaluated on the basis of a one-sided exact binomial test with a null DC rate of 15% versus 35% (power, 0.84; α, .10). Secondary end points were objective response (OR), progression-free survival, overall survival, duration of response, duration of stable disease, and safety.

RESULTS

Twenty-eight patients with 12 tumor types with BRAF alterations were enrolled from June 2016 to June 2021. All patients were evaluable for efficacy. Two patients with PR and four with SD16+ were observed for DC and OR rates of 21% (90% CI, 12 to 100) and 7% (95% CI, 1 to 24), respectively. The null hypothesis of 15% DC rate was not rejected (P = .24). Eight patients had at least one grade 3 adverse event or serious adverse event at least possibly related to regorafenib.

CONCLUSION

Regorafenib did not meet prespecified criteria to declare a signal of activity in patients with solid tumors with BRAF alterations.

Sunitinib in Patients With Breast Cancer With FGFR1 or FGFR2 Amplifications or Mutations: Results From the Targeted Agent and Profiling Utilization Registry Study

PURPOSE

The Targeted Agent and Profiling Utilization Registry Study is a phase II basket trial evaluating the antitumor activity of commercially available targeted agents in patients with advanced cancer and genomic alterations known to be drug targets. Results from cohorts of patients with metastatic breast cancer (BC) with FGFR1 and FGFR2 alterations treated with sunitinib are reported.

METHODS

Eligible patients had measurable disease, Eastern Cooperative Oncology Group performance status 0-2, adequate organ function, and no standard treatment options. Simon's two-stage design was used with a primary end point of disease control (DC), defined as objective response (OR) or stable disease of at least 16 weeks duration (SD16+) according to RECIST v1.1. Secondary end points included OR, progression-free survival, overall survival, duration of response, duration of stable disease, and safety.

RESULTS

Forty patients with BC with FGFR1 (N = 30; amplification only n = 26, mutation only n = 1, both n = 3) or FGFR2 (N = 10; amplification only n = 2, mutation only n = 6, both n = 2) alterations were enrolled. Three patients in the FGFR1 cohort were not evaluable for efficacy; all patients in the FGFR2 cohort were evaluable. For the FGFR1 cohort, two patients with partial response and four with SD16+ were observed for DC and OR rates of 27% (90% CI, 13 to 100) and 7% (95% CI, 1 to 24), respectively. The null hypothesis of 15% DC rate was not rejected (P = .169). No patients achieved DC in the FGFR2 cohort (P = 1.00). Thirteen of the 40 total patients across both cohorts had at least one grade 3-4 adverse event or serious adverse event at least possibly related to sunitinib.

CONCLUSION

Sunitinib did not meet prespecified criteria to declare a signal of antitumor activity in patients with BC with either FGFR1 or FGFR2 alterations. Other treatments and clinical trials should be considered for these patient populations.

Pembrolizumab in Patients With Tumors With High Tumor Mutational Burden: Results From the Targeted Agent and Profiling Utilization Registry Study

PURPOSE

The Targeted Agent and Profiling Utilization Registry (TAPUR) Study is a pragmatic basket trial evaluating antitumor activity of approved targeted agents in patients with advanced cancers harboring potentially actionable genomic alterations. Data from cohorts of patients with high tumor mutational burden (HTMB, defined as ≥9 mutations per megabase) with advanced colorectal cancer (CRC) and other advanced cancers treated with pembrolizumab are reported.

METHODS

Eligible patients were 18 years and older with measurable tumors and a lack of standard treatment options, an Eastern Cooperative Oncology Group performance status of 0-1, and adequate organ function. The primary end point was disease control (DC), defined as complete or partial response or stable disease (SD) of at least 16-weeks duration. For the CRC cohort, Simon's two-stage design with a null DC rate of 15% versus 35% (power = 0.85; α = .10) was used. Low accruing histology-specific cohorts were collapsed into one histology-pooled (HP) cohort. For the HP cohort, the null hypothesis of a DC rate of 15% was rejected if the lower limit of a one-sided 90% CI was >15%. Secondary end points included objective response (OR), safety, progression-free survival, overall survival, duration of response, and duration of SD.

RESULTS

Seventy-seven patients with HTMB with CRC (n = 28) or advanced cancers (n = 49) were treated with pembrolizumab. For the CRC cohort, the DC rate was 31% (P = .04) and the OR rate was 11%. For the HP cohort, the DC rate was 45% (one-sided 90% CI, 35 to 100) and the OR rate was 26%. The null hypothesis of a 15% DC rate was rejected for both cohorts. Twelve of 77 patients experienced treatment-related grade 3 adverse events (AEs) or serious AEs, including two deaths.

CONCLUSION

Pembrolizumab demonstrated antitumor activity in pretreated patients with advanced cancers and HTMB.

Nivolumab Plus Ipilimumab in Patients With Solid Tumors With ATM Mutations: Results From the Targeted Agent and Profiling Utilization Registry (TAPUR) Study

PURPOSE

The Targeted Agent and Profiling Utilization Registry Study is a phase II basket study evaluating the antitumor activity of commercially available targeted agents in patients with advanced cancers with genomic alterations known to be drug targets. Results of a cohort of patients with solid tumors with ATM mutations treated with nivolumab plus ipilimumab are reported.

METHODS

Eligible patients had measurable disease (RECIST v.1.1), Eastern Cooperative Oncology Group performance status 0-2, adequate organ function, and no standard treatment options. Primary end point was disease control (DC), defined as complete (CR) or partial (PR) response or stable disease (SD) of at least 16 weeks duration (SD16+). Low-accruing histology-specific cohorts with ATM mutations treated with nivolumab plus ipilimumab were collapsed into a single histology-pooled cohort for this analysis. The results were evaluated based on a one-sided exact binomial test with a null DC rate of 15% versus 35% (power = .84; α = .10). Secondary end points were objective response (OR), progression-free survival, overall survival, duration of response, duration of SD, and safety.

RESULTS

Twenty-nine patients with 10 tumor types with ATM mutations were enrolled from January 2018 to May 2020. One patient was not evaluable for efficacy. One CR, three PR, and three SD16+ were observed for DC and OR rates of 24% (P = .13; one-sided 90% CI: 14 to 100) and 14% (95% CI: 4 to 32), respectively. The null hypothesis of 15% DC rate was not rejected. Eleven patients had one treatment-related grade 3 adverse event (AE) or serious AE. There were two treatment-related patient deaths including immune-related encephalitis and respiratory failure.

CONCLUSION

Nivolumab plus ipilimumab did not meet prespecified criteria to declare a signal of activity in patients with solid tumors with ATM mutations.

Cobimetinib Plus Vemurafenib in Patients With Solid Tumors With BRAF Mutations: Results From the Targeted Agent and Profiling Utilization Registry Study

PURPOSE

The Targeted Agent and Profiling Utilization Registry Study is a phase II basket study evaluating antitumor activity of commercially available targeted agents in patients with advanced cancers with genomic alterations known to be drug targets. The results in a cohort of patients with solid tumors with BRAF mutations treated with cobimetinib plus vemurafenib are reported.

METHODS

Eligible patients had measurable disease (RECIST v.1.1), Eastern Cooperative Oncology Group performance status 0-2, adequate organ function, and no standard treatment options. The primary end point was disease control (DC), defined as complete response (CR) or partial response (PR) or stable disease of at least 16-weeks duration (SD16+). Low-accruing histology-specific cohorts with BRAF mutations treated with cobimetinib plus vemurafenib were collapsed into a single histology-pooled cohort for this analysis. The results were evaluated on the basis of a one-sided exact binomial test with a null DC rate of 15% versus 35% (power, .82; α, .10). The secondary end points were objective response (OR), progression-free survival, overall survival, duration of response, duration of stable disease, and safety.

RESULTS

Thirty-one patients with solid tumors with BRAF mutations were enrolled. Twenty-eight patients were evaluable for efficacy. Patients had tumors with BRAF V600E (n = 26), K601E (n = 2), or other (n = 3) mutations. Two patients with CR (breast and ovarian cancers; V600E), 14 with PR (13 V600E, one N581I), and three with SD16+ (two V600E, one T599_V600insT) were observed with a DC rate of 68% (P < .0001; one-sided 90% CI, 54 to 100) and an OR rate of 57% (95% CI, 37 to 76). Nineteen patients experienced ≥one drug-related grade 3-5 adverse event or serious adverse event including one death attributed to treatment-related kidney injury.

CONCLUSION

Cobimetinib plus vemurafenib showed antitumor activity in patients with advanced solid tumors with BRAF V600E mutations; additional study is warranted to confirm the antitumor activity in tumors with non-V600E BRAF mutations.

Pertuzumab Plus Trastuzumab in Patients With Lung Cancer With ERBB2 Mutation or Amplification: Results From the Targeted Agent and Profiling Utilization Registry Study

PURPOSE

The Targeted Agent and Profiling Utilization Registry Study is a pragmatic basket trial evaluating antitumor activity of commercially available targeted agents in patients with advanced cancers harboring potentially actionable genomic alterations. Data from a cohort of patients with lung cancer and ERBB2 mutation or amplification treated with pertuzumab plus trastuzumab (P + T) are reported.

METHODS

Eligible patients had advanced lung cancer of any histology, no standard treatment options, measurable disease (RECIST v1.1), Eastern Cooperative Oncology Group performance status 0-2, adequate organ function, and tumors with ERBB2 mutation or amplification. Simon's two-stage design was used with a primary end point of disease control (DC), defined as objective response (OR) per RECIST v. 1.1 or stable disease (SD) of at least 16 weeks duration (SD16+). Secondary end points included safety, duration of response, duration of SD, progression-free survival, and overall survival.

RESULTS

Twenty-eight patients with lung cancer (27 non-small-cell, 1 small-cell) and ERBB2 mutation (n = 15), ERBB2 amplification (n = 12), or both (n = 1) were enrolled from November 2016 to July 2020. All patients were evaluable for efficacy and toxicity. Three patients with partial response (two ERBB2 mutation; one both mutation and amplification) and seven patients with SD16+ (five ERBB2 mutation; two amplification) were observed for a DC rate of 37% (95% CI, 21 to 50; P = .005) and OR rate of 11% (95% CI, 2 to 28). Five patients had one or more grade 3 or 4 adverse or serious adverse events at least possibly related to P + T.

CONCLUSION

Combination P + T showed evidence of antitumor activity in heavily pretreated patients with non-small-cell lung cancer and ERBB2 mutation or amplification, particularly those with ERBB2 exon 20 insertion mutations.

Pertuzumab Plus Trastuzumab in Patients With Endometrial Cancer With ERBB2/3 Amplification, Overexpression, or Mutation: Results From the TAPUR Study

PURPOSE

The TAPUR Study is a pragmatic basket trial evaluating antitumor activity of commercially available targeted agents in patients with advanced cancers harboring potentially actionable genomic alterations. Data from a cohort of patients with endometrial cancer (EC) with ERBB2 or ERBB3 (ERBB2/3) amplification, overexpression, or mutation treated with pertuzumab plus trastuzumab (P + T) are reported.

METHODS

Eligible patients had advanced EC, no standard treatment options, measurable disease (RECIST v1.1), Eastern Cooperative Oncology Group performance status 0-2, adequate organ function, and tumors with ERBB2/3 amplification, overexpression, or mutation. Simon's two-stage design was used with a primary end point of disease control (DC), defined as objective response (OR) or stable disease (SD) of at least 16 weeks (SD16+) duration. Secondary end points include safety, duration of response, duration of SD, progression-free survival (PFS), and overall survival (OS).

RESULTS

Twenty-eight patients were enrolled from March 2017 to November 2019; all patients were evaluable for efficacy and toxicity. Seventeen patients had tumors with ERBB2/3 amplification and/or overexpression, eight with both ERBB2 amplification and ERBB2/3 mutations, and three with only ERBB2 mutations. Ten patients had DC (two partial response and eight SD16+); all 10 had ERBB2 amplification, and 6 of the 10 patients with DC had >1 ERBB2/3 alteration. DC and OR rates were 37% (95% CI, 21 to 50) and 7% (95% CI, 1 to 24), respectively; the median PFS and median OS were 16 weeks (95% CI, 10-28) and 61 weeks (95% CI, 24-105), respectively. One patient experienced a grade 3 serious adverse event (muscle weakness) at least possibly related to P + T.

CONCLUSION

P + T has antitumor activity in heavily pretreated patients with EC with ERBB2 amplification and warrants additional study.

Olaparib in Patients With Metastatic Prostate Cancer With BRCA1/2 Mutation: Results From the TAPUR Study

PURPOSE

The TAPUR Study is a phase II basket trial that aims to evaluate activity of approved targeted agents in patients with advanced cancers with potentially actionable genomic variants. Data from a cohort of patients with metastatic castrate-resistant prostate cancer (mCRPC) and BRCA1/2 mutations treated with olaparib are reported.

METHODS

Eligible patients with measurable mCRPC were matched to treatment according to protocol-specified genomic matching rules. Patients had no remaining standard treatment options, Eastern Cooperative Oncology Group performance status 0-2, and adequate organ function. Simon's two-stage design was used with a primary end point of disease control, defined as objective response or stable disease of at least 16-week duration. Secondary end points include radiographic progression-free survival, overall survival, duration of response, duration of stable disease, and safety.

RESULTS

Thirty patients with mCRPC with BRCA1/2 mutations were treated with olaparib. The disease control rate was 69% (95% CI, 51 to 81), and the objective response rate was 58% (95% CI, 37 to 77). The median radiographic progression-free survival and the median overall survival were 38.4 (95% CI, 16.3 to 52.1) weeks and 76.4 (95% CI, 49.3 to 106.0) weeks, respectively. Six of 30 (20%) patients experienced grade 3-4 adverse or serious adverse events including anemia, aspiration, decreased WBC count, and fatigue.

CONCLUSION

Olaparib has antitumor activity in patients with mCRPC with BRCA1/2 mutations and warrants further study to determine how to best integrate it into the standard treatment of patients with BRCA1/2-mutated prostate cancer.

Pertuzumab plus trastuzumab (P+T) in patients (pts) with biliary tract cancer (BTC) with ERBB2/3 amplification (amp), overexpression (oe), or mutation (mut): Results from the Targeted Agent and Profiling Utilization Registry (TAPUR) study

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Background: TAPUR is a phase II basket study evaluating antitumor activity of commercially available targeted agents in pts with advanced cancers with genomic alterations. Results in a cohort of pts with BTC with ERBB2/3 amp, oe, or mut treated with P+T are reported. Methods: Eligible pts had advanced BTC, no standard treatment (tx) options, measurable disease, ECOG Performance Status (PS) 0-2, and adequate organ function. Genomic testing was done in CLIA-certified, CAP-accredited labs. Dosing of P was 840 mg IV over 60 minutes (m), then 420 mg IV over 30-60 m Q3 weeks (wks); T was 8 mg/kg IV over 90 m, then 6 mg/kg IV over 30-60 m Q3 wks until disease progression. Primary end point was disease control (DC), defined as complete (CR) or partial (PR) response per RECIST v. 1.1, or stable disease (SD) at 16+ wks (SD16+). Simon 2-stage design tested the null DC rate of 15% vs. 35% (power = 0.85; α = 0.10). If ≥2 of 10 pts in stage 1 has DC, 18 more pts are enrolled; otherwise, cohort is closed for futility. If ≥7 of 28 pts has DC, the null DC rate is rejected. Secondary end points were progression-free survival (PFS), overall survival (OS), duration of response (DOR), duration of SD and safety. DOR is defined as time from pt’s first documented objective response (OR) to progressive disease (PD). Duration of SD is defined as time from start of tx to PD. Results: 29 pts with BTC (15 gallbladder (GB), 11 biliary duct (BD), 3 ampulla of Vater) and ERBB2/3 amp, oe, or mut were enrolled from Feb 2017 to Jan 2022. Median (med) age was 66 years (yrs) (range, 34-83 yrs). 66% of pts were female; 52% were White, 21% were Black/African American, 10% were Asian/Asian American; 83% were not Hispanic or Latino. 83% of pts had ECOG PS 0-1 and 48% had ≥3 prior systemic regimens. 1 pt was not evaluable and excluded from efficacy analysis. The table shows efficacy outcomes. 1 pt had CR (GB; ERBB2 amp; DOR: 71.1 wks), 8 pts had PR (6 GB/2 BD; 5 ERBB2 amp; 2 ERBB2 mut; 1 ERBB3 mut/ ERBB2 amp; med DOR: 30.4 wks (4.4 to 68.9 wks)) and 2 pts had SD16+. 4 pts with a KRAS mut did not achieve OR or SD16+. 4 pts had a Grade 3 drug-related adverse or serious adverse event (SAE): anemia, diarrhea, infusion related reaction (SAE), and fatigue. Conclusions: P+T demonstrated antitumor activity in pts with advanced BTC with ERBB2/3 alterations. These data, along with results previously reported by other studies, support continued study of P+T in pts with ERBB2 amplified BTC tumors. Clinical trial information: NCT02693535 . [Table: see text]

Olaparib (O) in patients (pts) with colorectal cancer (CRC) with ATM mutation (mut): Results from the Targeted Agent and Profiling Utilization Registry (TAPUR) study

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Background: TAPUR is a phase II basket study evaluating antitumor activity of commercially available targeted agents in pts with advanced cancers with genomic alterations. Results in a cohort of pts with CRC with ATM mut treated with O are reported. Methods: Eligible pts had advanced CRC with ATM mut, no standard treatment (tx) options, measurable disease, ECOG Performance Status (PS) 0-2, and adequate organ function. Genomic testing was done in CLIA-certified, CAP-accredited labs. Recommended dosing for O was 300 mg twice daily (tablets) or 400 mg twice daily (capsules) until disease progression. Primary end point was disease control (DC), defined as complete or partial (PR) response per RECIST v. 1.1, or stable disease (SD) at 16+ weeks (wks) (SD16+). Simon 2-stage design tested the null DC rate of 15% vs. 35% (power = 0.85; α = 0.10). If ≥2 of 10 pts in stage 1 has DC, 18 more pts are enrolled; otherwise, cohort is closed for futility. If ≥7 of 28 pts has DC, the null DC rate is rejected. Secondary end points were progression-free survival (PFS), overall survival (OS), duration of response (DOR), duration of SD, and safety. DOR is defined as time from the pt’s first documented objective response (OR) until progressive disease (PD). Duration of SD is defined as time from start of tx to PD. Results: 30 pts with CRC and ATM mut were enrolled from Sept 2016 to Aug 2019. 3 pts were not included in efficacy outcomes: 2 pts had no post-baseline tumor evaluation; 1 pt was found to be ineligible after receiving 1 dose. 1 PR ( ATM P938fs*11 and RAD50 variant of unknown significance (VUS); DOR was 18.6 wks) and 3 SD16+ ( ATM R1875*, splice site 4237-11_4241del16, E522*; duration of SD was 19.7, 25.3 and 27.0 wks, respectively) were observed for DC rate of 23% (95% CI, 6% to 39%) and OR rate of 4% (95% CI, 0.1% to 19%). The null DC rate was not rejected (p=0.38). 6/30 pts had a BRCA2 co-alteration, but none of these pts achieved OR or SD16+; no pts had a BRCA1 co-alteration; aside from the pt with PR and RAD50 VUS, only 1 other pt who achieved OR or SD16+ had a co-alteration among the other homologous recombination-related genes examined ( ATR VUS). 7 pts had ≥1 Grade 3 adverse or serious adverse event (SAE) at least possibly related to O, including urinary tract infection, white blood cell decreased, febrile neutropenia (SAE), anemia (1 SAE), lung infection (SAE), fatigue (SAE), and nausea (SAE). Conclusions: Monotherapy O does not show sufficient antitumor activity in pts with advanced CRC with ATM mut to warrant further study. Clinical trial information: NCT02693535 . [Table: see text]

Cobimetinib Plus Vemurafenib in Patients With Colorectal Cancer With BRAF Mutations: Results From the Targeted Agent and Profiling Utilization Registry (TAPUR) Study

PURPOSE

TAPUR is a phase II basket trial evaluating the antitumor activity of commercially available targeted agents in patients with advanced cancer and genomic alterations known to be drug targets. The results of a cohort of patients with colorectal cancer (CRC) with BRAF mutations treated with cobimetinib (C) plus vemurafenib (V) are reported.

METHODS

Eligible patients had advanced CRC, no standard treatment options, measurable disease (RECIST), Eastern Cooperative Oncology Group performance status 0-2, adequate organ function, tumors with BRAF V600E/D/K/R mutations, and no MAP2K1/2, MEK1/2, or NRAS mutations. C was taken 60 mg orally once daily for 21 days followed by seven days off, and V was taken 960 mg orally twice daily. Simon's two-stage design was used with a primary study end point of objective response or stable disease of at least 16 weeks duration. Secondary end points were progression-free survival, overall survival, and safety.

RESULTS

Thirty patients were enrolled from August 2016 to August 2018; all had CRC with a BRAF V600E mutation except one patient with a BRAF K601E mutation. Three patients were not evaluable for efficacy. Eight patients with partial responses and six patients with stable disease of at least 16 weeks duration were observed for disease control and objective response rates of 52% (95% CI, 35 to 65) and 30% (95% CI, 14 to 50), respectively. The null hypothesis of 15% disease control rate was rejected ( P < .0001). Thirteen patients had at least one grade 3 adverse event or serious adverse event at least possibly related to C + V: anemia, decreased lymphocytes, dyspnea, diarrhea, elevated liver enzymes, fatigue, hypercalcemia, hypophosphatemia, rash, photosensitivity, and upper gastrointestinal hemorrhage.

CONCLUSION

The combination of C + V has antitumor activity in heavily pretreated patients with CRC with BRAF mutations.

Pertuzumab Plus Trastuzumab in Patients With Colorectal Cancer With ERBB2 Amplification or ERBB2/3 Mutations: Results From the TAPUR Study

PURPOSE

The TAPUR Study is a pragmatic phase II basket trial evaluating antitumor activity of commercially available targeted agents in patients with advanced cancers harboring potentially actionable genomic alterations. Data from two cohorts of patients with colorectal cancer (CRC) with either ERBB2 amplifications or ERBB2 or ERBB3 (ERBB2/3) mutations treated with pertuzumab plus trastuzumab (P + T) are reported.

METHODS

Eligible patients with measurable CRC were selected for treatment with P + T according to protocol-specified genomic matching rules. Patients had no remaining standard treatment options, Eastern Cooperative Oncology Group performance status 0-2, and adequate organ function. Simon's two-stage design was used with a primary study end point of disease control (DC; objective response [OR] or stable disease of at least 16 weeks duration [SD16+]). Secondary end points include safety, response duration, progression-free survival (PFS), and overall survival (OS).

RESULTS

Thirty-eight patients with CRC with ERBB2 amplification (N = 28) or ERBB2/ 3 mutations (N = 10) were treated with P + T. For the ERBB2 amplification cohort, DC and OR were observed in 54% and 25% of patients, respectively; the median PFS and median OS (95% CIs) were 17.2 (11.1 to 27.4) weeks and 60.0 (32.1 to 102.3) weeks, respectively. For the ERBB2/ 3 mutation cohort, DC and OR were observed in 10% and 0% of patients, respectively; the median PFS and median OS were 9.6 (5.1 to 16.0) weeks and 28.8 (7.6 to 146.3) weeks, respectively. Four of 38 patients experienced grade 3 adverse events or serious adverse events including anemia, infusion reaction, diarrhea, left ventricular systolic dysfunction, and decreased lymphocyte count.

CONCLUSION

Although P + T treatment does not appear to have antitumor activity in CRC with ERBB2/3 mutations, this combination has antitumor activity in patients with CRC with ERBB2 amplification and warrants further study.

Abstract CT110: Olaparib (O) in patients (pts) with solid tumors with ATM mutation or deletion: Results from the Targeted Agent and Profiling Utilization Registry (TAPUR) Study

Background: TAPUR is a phase II basket study evaluating anti-tumor activity of commercially available targeted agents in pts with advanced cancers with specific genomic alterations. Results in a cohort of pts with solid tumors with ATM mutation (mut) or deletion (del) treated with O are reported.

Methods: Eligible pts had solid tumors, no standard treatment (tx) options, measurable disease, ECOG Performance Status (PS) 0-2, and adequate organ function. Genomic testing was performed in CLIA-certified, CAP-accredited site selected labs. Pts received O tablets (300mg) or capsules (400mg) orally twice daily until disease progression. Low accruing histology-specific cohorts with the same genomic alteration were collapsed into one histology-pooled cohort for this analysis. Primary endpoint was disease control (DC) (complete (CR) or partial (PR) response or stable disease at 16+ wks (SD16+)) (RECIST v1.1). For histology-specific cohorts a Simon 2-stage design with a null DC rate of 15% vs. 35% (power = 0.85; α = 0.10) requires 28 pts with futility stopping after 10 pts. For histology-pooled cohorts with sample size &gt; 28, if the lower limit of a one-sided 90% CI is &gt;15%, the null hypothesis of a DC rate of 15% is rejected. 2-sided 95% CIs were used for other efficacy endpoint estimates. Secondary endpoints were progression-free survival (PFS), overall survival (OS) and safety.

Results: 39 pts with solid tumors (17 histologies) with ATM mut (n=36) or del (n=3) were enrolled from 6/2016 to 1/2019. 3 pts were unevaluable for efficacy. Table 1 shows demographics and outcomes. 1 CR (prostate), 2 PR (unknown primary) and 6 SD16+ were observed in pts with ATM mut for a DC rate of 25% (90% CI: 16%, 100%) and an OR rate of 8% (95% CI: 2%, 23%). The null DC rate was rejected. 9 pts had ≥1 Grade 3 tx-related adverse or serious adverse event related to O.

Conclusions: Monotherapy O showed evidence of anti-tumor activity in pts with various solid tumors with ATM mut.

Table 1. Demographics and Baseline Characteristics (N=39); Efficacy Outcomes (N=36); Toxicity Outcomes (N=39) Median (Med) age, years (range) 65 (35, 77) Female, % 46 ECOG PS, % 0 33 1 59 2 8 Prior systemic regimens, % 0 3 1 8 2 15 ≥3 74 DC rate, % (OR or SD 16+) (1-sided 90% CI) 25 (16, 100) OR rate, % (95% CI) 8 (2, 23) Med PFS, wks (95% CI) 8.4 (8.0, 15.9) Med OS, wks (95% CI) 40.4 (30.3, 50.7) Med duration OR (range), wks 18.9 (4.3, 24.4) Med duration SD16+ (range), wks 27.3 (19.4, 31.0) Number of pts1 with treatment-related adverse or serious adverse events (all Grade 3) AE2 9 SAE3 4 1Patients may have experienced one or more events2anemia, anorexia, dehydration, fatigue, hypokalemia, nausea 3colitis, dizziness, lung infection, proteinuria, urinary tract infection/obstruction

Citation Format: Kathryn F. Mileham, Michael Rothe, Pam K. Mangat, Elizabeth Garrett-Mayer, Eddy S. Yang, Olatunji B. Alese, Angela Jain, Herbert L. Duvivier, Phillip Palmbos, Eugene R. Ahn, Jeanny B. Aragon-Ching, Kathleen W. Beekman, Deepti Behl, Funda Meric-Bernstam, Rodolfo Gutierrez, Amy Sanford, Ramya Thota, Michael Zakem, Song Zhao, Raegan O'Lone, Gina N. Grantham, Susan Halabi, Richard L. Schilsky. Olaparib (O) in patients (pts) with solid tumors with ATM mutation or deletion: Results from the Targeted Agent and Profiling Utilization Registry (TAPUR) Study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT110.

Temsirolimus (T) in patients (pts) with solid tumors with mTOR mutation: Results from the Targeted Agent and Profiling Utilization Registry (TAPUR) Study

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Background: TAPUR is a phase II basket study evaluating anti-tumor activity of commercially available targeted agents in pts with advanced cancers with genomic alterations. Results in a cohort of solid tumor pts with mTOR mutation (mut) treated with T are reported. Methods: Eligible pts had solid tumors, no standard treatment (tx) options, measurable disease, ECOG Performance Status (PS) 0-2, and adequate organ function. Genomic testing was performed in CLIA-certified, CAP-accredited site selected labs. Pts matched to T had various solid tumors with mTOR mut. After antihistamine pre-treatment, 25 mg T was infused over 30-60 minutes weekly until disease progression. Primary endpoint was disease control (DC), defined as complete (CR) or partial (PR) response, or stable disease at 16+ weeks (wks) (SD 16+) (RECIST v1.1). Low accruing histology-specific cohorts with the same genomic alteration and tx were collapsed into a single histology-pooled cohort for this analysis. For histology-pooled cohorts with sample size ≤28, the results are evaluated based on a one-sided exact binomial test with a null DC rate of 15% vs. 35% (α = 0.10 and power=0.86 for N = 26) and one-sided 90% confidence interval (CI). Other efficacy endpoint estimates are presented with two-sided 95% CIs. Secondary endpoints were progression-free survival (PFS), overall survival (OS) and safety. Results: 29 pts with solid tumors (11 histologies) with mTOR mut were enrolled from June 2016 to June 2020. 3 pts were not evaluable (2 pts, no post-baseline tumor eval; 1 pt, no measurable disease) and excluded from efficacy analyses. The Table shows demographics and outcomes. 2 PR and 10 SD16+ were observed for a DC rate of 46% (one-sided 90% CI: 32% to 100%) and an objective response (OR) rate of 8% (95% CI: 1% to 25%); the null hypothesis of a 15% DC rate is rejected (p<0.001). 5/10 pts with SD16+ had CRC or biliary cancer. Of the 2 pts with PR, one had uterine cancer and T1977R mut and the other had head and neck cancer and I1636V mut. The durations of PR were 12.3 and 23.9 wks, respectively, and median duration of SD was 34.5 wks (range: 18.7, 90.0) for pts with SD16+. 8 pts experienced grade 3 or grade 4 AEs or SAEs at least possibly related to T, including acute kidney injury, epistaxis, hyperglycemia, hypertension, hypertriglyceridemia, mucositis, leukopenia, thrombocytopenia, and pneumonitis. Conclusions: Monotherapy T showed evidence of anti-tumor activity in pts with advanced solid tumors with mTOR mut. Additional study is warranted to confirm the efficacy of T in pts with mTOR mut. Clinical trial information: NCT02693535. [Table: see text]

Temsirolimus (T) in patients (pts) with colorectal cancer (CRC) with PIK3CA mutation: Results from the Targeted Agent and Profiling Utilization Registry (TAPUR) study

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Background: TAPUR is a phase II basket study evaluating anti-tumor activity of commercially available targeted agents in pts with advanced cancers with genomic alterations. Results in a cohort of CRC pts with PIK3CA mutation treated with T are reported. Methods: Eligible pts had advanced CRC with PIK3CA mutation reported by a genomic test performed in a CLIA-certified, CAP-accredited site selected lab, no standard treatment options, measurable disease, ECOG performance status (PS) 0-2, and adequate organ function. Use of T was approved by the TAPUR Molecular Tumor Board in each case. After antihistamine pre-treatment, T was administered at 25 mg IV over 30-60 minutes weekly until disease progression. Primary endpoint was disease control (DC), defined as complete (CR) or partial (PR) response per RECIST v. 1.1, or stable disease at 16+ weeks (SD 16+). Simon 2-stage design tested the null DC rate of 15% vs. 35% (power = 0.85; α = 0.10). If ≥2 of 10 pts in stage 1 has DC, 18 more pts are enrolled; otherwise, the study stops for futility. If ≥7 of 28 pts has DC, the null DC rate is rejected. Secondary endpoints were progression-free survival (PFS), overall survival (OS) and safety. Results: 10 pts (60% male) with CRC with PIK3CA mutation were enrolled from November 2017 to May 2020. All were eligible for efficacy and toxicity. Demographics and outcomes are summarized in Table. No objective responses (OR) were observed. 1 pt had SD of 16.1 wks duration for a DC rate of 10% (95% CI: 0%, 45%); the null DC rate of 15% was not rejected (p=0.80). 6 pts had at least one grade 3-4 adverse or serious adverse event (AE/SAE) at least possibly related to T, including acute kidney injury, dehydration, decreased platelet count hypertriglyceridemia, mucositis, neutropenia, and scrotal and penile edema. Conclusions: Monotherapy T does not have sufficient clinical activity in CRC pts with PIK3CA mutation for continued evaluation in this pt population. Other treatments should be considered for these pts, including treatments offered in clinical trials. Clinical trial information: NCT02693535. [Table: see text]

Nivolumab plus ipilimumab (N+I) in patients (pts) with colorectal cancer (CRC) with high tumor mutational burden (hTMB): Results from the Targeted Agent and Profiling Utilization Registry (TAPUR) study

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Background: TAPUR is a phase II basket study evaluating the anti-tumor activity of commercially available targeted agents in pts with advanced cancers with genomic alterations. Results in a cohort of CRC pts with hTMB treated with N+I are reported. Methods: Eligible pts had advanced CRC, no available standard treatment options, measurable disease, ECOG performance status (PS) 0-2, adequate organ function and no prior immune checkpoint inhibitor treatment. PDL-1 expression testing was not required. Genomic testing was performed in CLIA-certified, CAP-accredited site selected labs. hTMB was defined a priori as ≥9 mutations/megabase (Muts/Mb) reported by a FoundationOne test (n=7) or other tests (n=5) if approved by the Molecular Tumor Board. Pts received N 1 mg/kg IV every 3 weeks (wks) for 4 doses in combination with I 3 mg/kg every 3 wks for 4 doses. N was then continued at 240 mg every 2 wks or 480 mg every 4 wks until disease progression. Primary endpoint was disease control (DC), defined as complete (CR) or partial (PR) response, or stable disease at 16+ wks (SD 16+). Simon 2-stage design tested the null DC rate of 15% vs. 35% (power = 0.85; α = 0.10). If ≥2 of 10 pts in stage 1 has DC, 18 more pts are enrolled; otherwise, the study stops for futility. If ≥7 of 28 pts has DC, the null DC rate is rejected. Secondary endpoints were progression-free survival (PFS), overall survival (OS) and safety. Results: 12 pts (9 male) with CRC with hTMB in tissue biopsy were enrolled from February 2018 to May 2020; 2 pts were not evaluable and excluded from efficacy analyses. All pts were evaluated for toxicity. TMB ranged from 9 to 233 Muts/Mb (median 13). Demographics and outcomes are summarized in the table below. Tumor microsatellite (MS) status was reported stable for 11 pts and indeterminate for 1 pt. 1 PR (88.1 wks duration, tumor 11 Muts/Mb, MS stable, PDL-1 expression not reported, KRAS mutant) and 0 pts with SD16+ were observed for a DC and OR rate of 10% (95% CI: 0%, 45%); the null DC rate of 15% was not rejected (p=0.80) and the cohort closed due to futility. 4 pts had at least one grade 3-4 adverse or serious adverse event (AE/SAE) at least possibly related to N+I including myasthenia gravis, diarrhea, glucose intolerance, hyperglycemia, and small intestinal obstruction. Conclusions: Combination therapy with N+I does not have sufficient clinical activity in pts with MS stable, hTMB CRC for further evaluation in this pt population. Other treatments should be considered for these pts, including treatments offered in clinical trials. Clinical trial information: NCT02693535. [Table: see text]