354 Lenvatinib and pembrolizumab in advanced endometrial carcinoma (EC): long-term efficacy and safety update from a phase 1b/2 study

Background

Lenvatinib is a multikinase inhibitor of VEGFR 1–3, FGFR 1–4, PDGFRα, RET, and KIT. Pembrolizumab is an anti-programmed death-1 monoclonal antibody. We previously reported results from a cohort of 108 patients with metastatic EC (data cutoff date, January 10, 2019) who received lenvatinib + pembrolizumab as part of an ongoing multicenter, open-label, phase 1b/2 study evaluating the combination treatment in patients with selected solid tumors (NCT02501096). Lenvatinib + pembrolizumab showed a tolerable safety profile and promising antitumor activity per immune-related (ir) Response Evaluation Criteria In Solid Tumors (RECIST) by investigator assessment, including an objective response rate (ORR) of 38.9% (95% confidence interval [CI], 29.7–48.7), median progression-free survival (PFS) of 7.4 months (95% CI, 5.3–8.7), and median overall survival (OS) of 16.7 months (95% CI, 15.0-not estimable).1 Here we present updated efficacy and safety data (data cutoff date: August 18, 2020).

Methods

Patients included in the EC cohort had histologically confirmed, measurable metastatic EC and had received ≤2 prior chemotherapies (unless discussed with the sponsor). Patients received lenvatinib (20 mg orally once daily) and pembrolizumab (200 mg intravenously once every 3 weeks). The phase 2 efficacy endpoints included ORR, PFS, OS, and duration of response. Tumor assessments for primary and secondary endpoints were evaluated by investigators per irRECIST.

Results

The 108 patients from the key efficacy analysis set for the previously reported results were all included in these updated analyses. Median follow-up duration for the study was 34.7 months. Efficacy outcomes are summarized in table 1. Treatment-related adverse events (TRAEs) occurred in 104 (96%) patients (94 [87%] grade ≤3, 10 [9%] grade ≥4). TRAEs led to study-drug interruption of 1 or both drugs in 80 (74.1%) patients and dose reductions of lenvatinib in 73 (67.6%) patients; 23 (21.3%) patients discontinued 1 or both drugs due to a TRAE. The most common grade ≥3 TRAEs were hypertension (33.3%), lipase increased (9.3%), fatigue (8.3%), and diarrhea (7.4%).

Abstract 354 Table 1

Conclusions

With extended follow-up, our updated efficacy analysis continued to show clinical benefit in patients with metastatic EC who received lenvatinib + pembrolizumab. Moreover, the combination had a manageable safety profile that was generally consistent with the established safety profiles of the individual monotherapies. No new safety signals were detected. A phase 3 study of lenvatinib + pembrolizumab versus treatment of physician’s choice in advanced endometrial cancer further supports the lasting clinical benefits observed in our study.2

Trial Registration

www.clinicaltrials.gov NCT02501096

References

Makker V, Taylor MH, Aghajanian C, et al. Lenvatinib plus pembrolizumab in patients with advanced endometrial cancer. J Clin Oncol 2020;38(26):2981–2992.

Makker V, Colombo N, Casado Herráez A, et al. A multicenter, open-label, randomized, phase 3 study to compare

Ethics Approval

This study was approved by the following ethics committees/institutional review boards (IRBs): Oregon Health & Sciences University IRB, IntegReview IRB, Memorial Sloan Kettering Cancer Center IRB, University of Pennsylvania Office of Regulatory Affairs IRB, Dana-Farber Cancer Institute IRB, The University of Chicago Biological Sciences Division IRB, University of Texas MD Anderson Cancer Center IRB, Western IRB, Quorum Review IRB, US Oncology, Inc. IRB, CEIm - Comité de Ética de la Investigación con Medicamentos, Regional Komite for Medisinsk og Helsefagli Forskningsetikk, and REC - Regional Committees for Medical and Health Research Ethics. All participants gave informed consent before taking part in this study.

Consent

No identifying information is contained in this abstract so no permission from participants is considered necessary.

Abstract LB013: Clinical validation of a targeted methylation-based multi-cancer early detection test

Introduction: A multi-cancer early detection (MCED) test as a complement to existing screening tests could increase the number of cancer cases detected in a population, potentially improving patient outcomes and survival as well as decreasing harmful and aggressive treatments. The Circulating Cell-free Genome Atlas study (CCGA; NCT02889978) was designed to develop and validate a blood-based MCED test analyzing plasma cell-free DNA (cfDNA) to detect cancer signals across multiple cancer types and simultaneously predict their signal origin. Here, the results of the third and final pre-specified CCGA validation sub-study for a refined MCED test in a large cohort in preparation for clinical use are reported. Methods: CCGA is a prospective, multicenter, case-control, observational study with longitudinal follow-up (overall population N=15,254). In this sub-study (n=5309), key primary objectives were to evaluate test performance for cancer signal detection (specificity, overall sensitivity, sensitivity by clinical stage) and signal origin prediction (accuracy). cfDNA from evaluable samples was analyzed using a targeted methylation bisulfite sequencing assay and a machine learning algorithm. The classifier was trained to target a specificity of 99.4% and locked before analysis of the independent validation set. Overall, 4077 participants comprised the independent validation set with confirmed status (cancer: n=2823; non-cancer: n=1254 with non-cancer status confirmed at year-one follow-up). MCED test results are reported for this confirmed status set. Results: Mean (SD) age in the cancer and non-cancer groups was 62.6 (11.76) and 56.2 (12.63) years, respectively. Specificity for cancer signal detection was 99.5% (1248/1254; 95% confidence interval: 99.0-99.8%). Overall sensitivity for cancer signal detection was 51.5% (1453/2823; 49.6-53.3%); sensitivity increased with stage (Stage I: 16.8% [14.5-19.5%], Stage II: 40.4% [36.8-44.1%], Stage III: 77.0% [73.4-80.3%], Stage IV: 90.1% [87.5-92.2%]). Stage I-III sensitivity was 67.6% (593/877; 64.4-70.6%) in a pre-specified set of 12 high-signal cancers accounting for ~63% of annual US cancer deaths [1] and was 40.7% (863/2118; 38.7-42.9%) in all cancers. Cancer signals were detected across >50 cancer types [2]. Overall accuracy of signal origin prediction in true positives was 88.7% (87.0-90.2%). Conclusions: In this pre-specified, large-scale, clinical validation sub-study of CCGA, the MCED test detected cancer signals across >50 cancer types, which is critical to maximize the number of cancer cases detected in a population. This MCED test performed with high specificity and high accuracy of signal origin prediction. These data lay the foundation for population-scale clinical implementation of this test. 1.US Mortality Data 1969-2016 (www.seer.cancer.gov); based on 2015-2016. 2.Amin et al. CA Cancer J Clin. 2017;67:93e99.

Citation Format: Eric A. Klein, Donald Richards, Allen Cohn, Mohan Tummala, Rosanna Lapham, David Cosgrove, Gina Chung, Jessica Clement, Jingjing Gao, Nathan Hunkapiller, Arash Jamshidi, Kathryn Kurtzman, Michael V. Seiden, Charles Swanton, Minetta C. Liu. Clinical validation of a targeted methylation-based multi-cancer early detection test [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB013.

Clinical validation of a targeted methylation-based multi-cancer early detection test using an independent validation set

BACKGROUND

A multi-cancer early detection (MCED) test used to complement existing screening could increase the number of cancers detected through population screening, potentially improving clinical outcomes. The Circulating Cell-free Genome Atlas study (CCGA; NCT02889978) was a prospective, case-controlled, observational study and demonstrated that a blood-based MCED test utilizing cell-free DNA (cfDNA) sequencing in combination with machine learning could detect cancer signals across multiple cancer types and predict cancer signal origin (CSO) with high accuracy. The objective of this third and final CCGA substudy was to validate an MCED test version further refined for use as a screening tool.

PATIENTS AND METHODS

This pre-specified substudy included 4077 participants in an independent validation set (cancer: n = 2823; non-cancer: n = 1254, non-cancer status confirmed at year-one follow-up). Specificity, sensitivity, and CSO prediction accuracy were measured.

RESULTS

Specificity for cancer signal detection was 99.5% [95% confidence interval (CI): 99.0% to 99.8%]. Overall sensitivity for cancer signal detection was 51.5% (49.6% to 53.3%); sensitivity increased with stage [stage I: 16.8% (14.5% to 19.5%), stage II: 40.4% (36.8% to 44.1%), stage III: 77.0% (73.4% to 80.3%), stage IV: 90.1% (87.5% to 92.2%)]. Stage I-III sensitivity was 67.6% (64.4% to 70.6%) in 12 pre-specified cancers that account for approximately two-thirds of annual USA cancer deaths and was 40.7% (38.7% to 42.9%) in all cancers. Cancer signals were detected across >50 cancer types. Overall accuracy of CSO prediction in true positives was 88.7% (87.0% to 90.2%).

CONCLUSION

In this pre-specified, large-scale, clinical validation substudy, the MCED test demonstrated high specificity and accuracy of CSO prediction and detected cancer signals across a wide diversity of cancers. These results support the feasibility of this blood-based MCED test as a complement to existing single-cancer screening tests.

CLINICAL TRIAL NUMBER

NCT02889978.

A Phase 2 Randomized Placebo-Controlled Adjuvant Trial of GI-4000, a Recombinant Yeast Expressing Mutated RAS Proteins in Patients with Resected Pancreas Cancer

Purpose: GI-4000, a series of recombinant yeast expressing four different mutated RAS proteins, was evaluated in subjects with resected ras-mutated pancreas cancer. Methods: Subjects (n = 176) received GI-4000 or placebo plus gemcitabine. Subjects' tumors were genotyped to identify which matched GI-4000 product to administer. Immune responses were measured by interferon-γ (IFNγ) ELISpot assay and by regulatory T cell (Treg) frequencies on treatment. Pretreatment plasma was retrospectively analyzed by matrix-assisted laser desorption/ionization-time-of-flight (MALDI-ToF) mass spectrometry for proteomic signatures predictive of GI-4000 responsiveness. Results: GI-4000 was well tolerated, with comparable safety findings between treatment groups. The GI-4000 group showed a similar pattern of median recurrence-free and overall survival (OS) compared with placebo. For the prospectively defined and stratified R1 resection subgroup, there was a trend in 1 year OS (72% vs. 56%), an improvement in OS (523.5 vs. 443.5 days [hazard ratio (HR) = 1.06 [confidence interval (CI): 0.53-2.13], p = 0.872), and increased frequency of immune responders (40% vs. 8%; p = 0.062) for GI-4000 versus placebo and a 159-day improvement in OS for R1 GI-4000 immune responders versus placebo (p = 0.810). For R0 resection subjects, no increases in IFNγ responses in GI-4000-treated subjects were observed. A higher frequency of R0/R1 subjects with a reduction in Tregs (CD4⁺/CD45RA⁺/Foxp3^low) was observed in GI-4000-treated subjects versus placebo (p = 0.033). A proteomic signature was identified that predicted response to GI-4000/gemcitabine regardless of resection status. Conclusion: These results justify continued investigation of GI-4000 in studies stratified for likely responders or in combination with immune check-point inhibitors or other immunomodulators, which may provide optimal reactivation of antitumor immunity. ClinicalTrials.gov Number: NCT00300950.

Efficacy and Safety of Atezolizumab Plus Bevacizumab Following Disease Progression on Atezolizumab or Sunitinib Monotherapy in Patients with Metastatic Renal Cell Carcinoma in IMmotion150: A Randomized Phase 2 Clinical Trial

BACKGROUND

The use of immune checkpoint inhibitors combined with vascular endothelial growth factor (VEGF)-targeted therapy as second-line treatment for metastatic clear cell renal cancer (mRCC) has not been evaluated prospectively.

OBJECTIVE

To evaluate the efficacy and safety of atezolizumab + bevacizumab following disease progression on atezolizumab or sunitinib monotherapy in patients with mRCC.

DESIGN, SETTING, AND PARTICIPANTS

IMmotion150 was a multicenter, randomized, open-label, phase 2 study of patients with untreated mRCC. Patients randomized to the atezolizumab or sunitinib arm who had investigator-assessed progression as per RECIST 1.1 could be treated with second-line atezolizumab + bevacizumab.

INTERVENTION

Patients received atezolizumab 1200 mg intravenously (IV) plus bevacizumab 15 mg/kg IV every 3 wk following disease progression on either atezolizumab or sunitinib monotherapy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The secondary endpoints analyzed during the second-line part of IMmotion150 included objective response rate (ORR), progression-free survival (PFS), and safety. PFS was examined using Kaplan-Meier methods.

RESULTS AND LIMITATIONS

Fifty-nine patients in the atezolizumab arm and 78 in the sunitinib arm were eligible, and 103 initiated second-line atezolizumab + bevacizumab (atezolizumab arm, n = 44; sunitinib arm, n = 59). ORR (95% confidence interval [CI]) was 27% (19-37%). The median PFS (95% CI) from the start of second line was 8.7 (5.6-13.7) mo. The median event follow-up duration was 19.4 (12.9-21.9) mo among the 25 patients without a PFS event. Eighty-six (83%) patients had treatment-related adverse events; 31 of 103 (30%) had grade 3/4 events. Limitations were the small sample size and selection for progressors.

CONCLUSIONS

The atezolizumab + bevacizumab combination had activity and was tolerable in patients with progression on atezolizumab or sunitinib. Further studies are needed to investigate sequencing strategies in mRCC.

PATIENT SUMMARY

Patients with advanced kidney cancer whose disease had worsened during treatment with atezolizumab or sunitinib began second-line treatment with atezolizumab + bevacizumab. Tumors shrank in more than one-quarter of patients treated with this combination, and side effects were manageable.

Infigratinib in patients with advanced cholangiocarcinoma with FGFR2 gene fusions/translocations: the PROOF 301 trial

Cholangiocarcinoma is an aggressive malignancy with poor overall survival. Approximately 15% of intrahepatic cholangiocarcinomas contain FGFR alterations. Infigratinib is an oral FGFR 1-3 kinase inhibitor. Favorable results from a Phase II trial of infigratinib in advanced/metastatic FGFR-altered cholangiocarcinomas has led to its further investigation in the front-line setting. In this article we describe the design, objectives and rationale for PROOF 301, a Phase III multicenter, open label, randomized trial of infigratinib in comparison to standard of care gemcitabine and cisplatin in advanced/metastatic cholangiocarcinoma with FGFR2 translocations. The results of this study have the potential to define a new role for a chemotherapy-free, targeted therapy option in the front-line setting for these patients. Clinical Trial Registration: NCT03773302 (ClincalTrials.gov).

0190 Impact of Menopause-Related Sleep Fragmentation on Daytime Sleepiness and Neurobehavioral Performance: Results of an Experimental Model

Introduction

Cognitive performance may be adversely affected during the menopause transition from hot flash-induced sleep fragmentation even without changes in sleep duration. We examined the effects of experimentally-induced sleep fragmentation without shortened sleep duration on daytime sleepiness and neurobehavioral performance in women in a high and low estradiol (E2) state.

Methods

Seven pre-menopausal women (29.4 ± 3.8 years) participated in two 6-day inpatient studies repeated in a high-E2 (mid-to-late follicular phase) then low-E2 state (gonadotropin-releasing hormone agonist-induced E2 suppression - similar to levels during menopause) ~6 weeks apart. Sleep was uninterrupted on nights 1–2 [8-h time-in-bed (TIB)] and fragmented on nights 3–5 (9-h TIB) using an auditory stimulus delivered every 15 min that sustained wake for 2 minutes, producing 1-h total wake after sleep onset. Wakefulness was confirmed by event-markers during polysomnographically-recorded sleep episodes. Daytime subjective sleepiness (Karolinska Sleepiness Scale; KSS) and neurobehavioral performance (Psychomotor Vigilance Task; PVT) were assessed every 2–3 hours on study days 2–5. The effects of study day and E2 state on KSS scores and PVT measured reaction time (RT) and attentional failures (RT>500ms) were examined using linear mixed models.

Results

Participants reported feeling sleepier (+10%), had longer RTs (+22ms), and more attentional failures (+53%) after sleep fragmentation than after uninterrupted sleep (all p<0.001). While there was no main effect of E2 state, there was a differential effect of sleep fragmentation by E2 state on PVT, but not sleepiness, such that the increase in RT and attentional failures in response to sleep fragmentation was only observed in the high-E2 state (p<0.001).

Conclusion

Eight hours of total sleep time may not be sufficient to maintain subjective sleepiness and PVT performance levels when sleep is not consolidated. These findings have important implications for understanding the role of sleep and E2-modulated cognitive impairment during the menopause transition.

Support

This work was supported by the NIH: 5R01 AG053838-02 (HJ) and K24-HL105664 (EBK).

Randomized, double-blind, phase two study of ruxolitinib plus regorafenib in patients with relapsed/refractory metastatic colorectal cancer

BACKGROUND

The Janus kinase/signal transducer and activator of transcription (JAK-STAT) signaling pathway plays a key role in the systemic inflammatory response in many cancers, including colorectal cancer (CRC). This study evaluated the addition of ruxolitinib, a potent JAK1/2 inhibitor, to regorafenib in patients with relapsed/refractory metastatic CRC.

METHODS

In this two-part, multicenter, phase 2 study, eligible adult patients had metastatic adenocarcinoma of the colon or rectum; an Eastern Cooperative Oncology Group performance status of 0-2; received fluoropyrimidine, oxaliplatin, and irinotecan-based chemotherapy, an anti-vascular endothelial growth factor therapy (if no contraindication); and if KRAS wild-type (and no contraindication), an anti-epidermal growth factor receptor therapy; and progressed following the last administration of approved therapy. Patients who received previous treatment with regorafenib, had an established cardiac or gastrointestinal disease, or had an active infection requiring treatment were excluded. The study was conducted in 95 sites in North America, European Union, Asia Pacific, and Israel. After an open-label, safety run-in phase (part 1; ruxolitinib 20 mg twice daily [BID] plus regorafenib 160 mg once daily [QD]), the double-blind, randomized phase (part 2) was conducted wherein patients were randomized 1:1 to receive ruxolitinib 15 mg BID plus regorafenib 160 mg QD [ruxolitinib group] or placebo plus regorafenib 160 mg QD [placebo group]. Part 2 included substudy 1 (patients with high systemic inflammation, ie, C-reactive protein [CRP] >10 mg/L) and substudy 2 (patients with low systemic inflammation, ie, CRP ≤10 mg/L); the primary endpoint was overall survival (OS).

RESULTS

The study was terminated early; substudy 1 was terminated for futility at interim analysis and substudy 2 was terminated per sponsor decision. Ruxolitinib 20 mg BID was well tolerated in the safety run-in (n = 11). Overall, 396 patients were randomized (substudy 1: n = 175 [ruxolitinib group, n = 87; placebo group, n = 88]; substudy 2: n = 221 [ruxolitinib group, n = 110; placebo group, n = 111]). There was no significant difference in OS or progression-free survival (PFS) between treatments in substudy 1 (OS: hazard ratio [HR] = 1.040 [95% confidence interval: 0.725-1.492]; PFS: HR = 1.004 [0.724-1.391]) and substudy 2 (OS: HR = 0.767 [0.478-1.231]; PFS: HR = 0.787 [0.576-1.074]). The most common hematologic adverse event was anemia. No new safety signals with ruxolitinib were identified.

CONCLUSIONS

Although addition of ruxolitinib to regorafenib did not show increased safety concerns in patients with relapsed/refractory metastatic CRC, this combination did not improve OS/PFS vs. regorafenib plus placebo.

A randomized phase II trial of CRLX101 in combination with bevacizumab versus standard of care in patients with advanced renal cell carcinoma

BACKGROUND

Nanoparticle-drug conjugates enhance drug delivery to tumors. Gradual payload release inside cancer cells augments antitumor activity while reducing toxicity. CRLX101 is a novel nanoparticle-drug conjugate containing camptothecin, a potent inhibitor of topoisomerase I and the hypoxia-inducible factors 1α and 2α. In a phase Ib/2 trial, CRLX101 + bevacizumab was well tolerated with encouraging activity in metastatic renal cell carcinoma (mRCC). We conducted a randomized phase II trial comparing CRLX101 + bevacizumab versus standard of care (SOC) in refractory mRCC.

PATIENTS AND METHODS

Patients with mRCC and 2-3 prior lines of therapy were randomized 1 : 1 to CRLX101 + bevacizumab versus SOC, defined as investigator's choice of any approved regimen not previously received. The primary end point was progression-free survival (PFS) by blinded independent radiological review in patients with clear cell mRCC. Secondary end points included overall survival, objective response rate and safety.

RESULTS

In total, 111 patients were randomized and received ≥1 dose of drug (CRLX101 + bevacizumab, 55; SOC, 56). Within the SOC arm, patients received single-agent bevacizumab (19), axitinib (18), everolimus (7), pazopanib (4), sorafenib (4), sunitinib (2), or temsirolimus (2). In the clear cell population, the median PFS on the CRLX101 + bevacizumab and SOC arms was 3.7 months (95% confidence interval, 2.0-4.3) and 3.9 months (95% confidence interval 2.2-5.4), respectively (stratified log-rank P = 0.831). The objective response rate by IRR was 5% with CRLX101 + bevacizumab versus 14% with SOC (Mantel-Haenszel test, P = 0.836). Consistent with previous studies, the CRLX101 + bevacizumab combination was generally well tolerated, and no new safety signal was identified.

CONCLUSIONS

Despite promising efficacy data on the earlier phase Ib/2 trial of mRCC, this randomized trial did not demonstrate improvement in PFS for the CRLX101 + bevacizumab combination when compared with approved agents in patients with heavily pretreated clear cell mRCC. Further development in this disease is not planned.

CLINICAL TRIAL IDENTIFICATION

NCT02187302 (NIH).

Subgroup analysis in RAISE: a randomized, double-blind phase III study of irinotecan, folinic acid, and 5-fluorouracil (FOLFIRI) plus ramucirumab or placebo in patients with metastatic colorectal carcinoma progression

BACKGROUND

The RAISE phase III clinical trial demonstrated that ramucirumab + FOLFIRI improved overall survival (OS) [hazard ratio (HR) = 0.844, P = 0.0219] and progression-free survival (PFS) (HR = 0.793, P < 0.0005) compared with placebo + FOLFIRI for second-line metastatic colorectal carcinoma (mCRC) patients previously treated with first-line bevacizumab, oxaliplatin, and a fluoropyrimidine. Since some patient or disease characteristics could be associated with differential efficacy or safety, prespecified subgroup analyses were undertaken. This report focuses on three of the most relevant ones: KRAS status (wild-type versus mutant), age (<65 versus ≥65 years), and time to progression (TTP) on first-line therapy (<6 versus ≥6 months).

PATIENTS AND METHODS

OS and PFS were evaluated by the Kaplan-Meier analysis, with HR determined by the Cox proportional hazards model. Treatment-by-subgroup interaction was tested to determine whether treatment effect was consistent between subgroup pairs.

RESULTS

Patients with both wild-type and mutant KRAS benefited from ramucirumab + FOLFIRI treatment over placebo + FOLFIRI (interaction P = 0.526); although numerically, wild-type KRAS patients benefited more (wild-type KRAS: median OS = 14.4 versus 11.9 months, HR = 0.82, P = 0.049; mutant KRAS: median OS = 12.7 versus 11.3 months, HR = 0.89, P = 0.263). Patients with both longer and shorter first-line TTP benefited from ramucirumab (interaction P = 0.9434), although TTP <6 months was associated with poorer OS (TTP ≥6 months: median OS = 14.3 versus 12.5 months, HR = 0.86, P = 0.061; TTP <6 months: median OS = 10.4 versus 8.0 months, HR = 0.86, P = 0.276). The subgroups of patients ≥65 versus <65 years also derived a similar ramucirumab survival benefit (interaction P = 0.9521) (≥65 years: median OS = 13.8 versus 11.7 months, HR = 0.85, P = 0.156; <65 years: median OS = 13.1 versus 11.9 months, HR = 0.86, P = 0.098). The safety profile of ramucirumab + FOLFIRI was similar across subgroups.

CONCLUSIONS

These analyses revealed similar efficacy and safety among patient subgroups with differing KRAS mutation status, longer or shorter first-line TTP, and age. Ramucirumab is a beneficial addition to second-line FOLFIRI treatment for a wide range of patients with mCRC.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT01183780.

A Randomized, Phase II Trial of Cetuximab With or Without PX-866, an Irreversible Oral Phosphatidylinositol 3-Kinase Inhibitor, in Patients With Metastatic Colorectal Carcinoma

BACKGROUND

The phosphotidylinositol-3 kinase (PI3K)/serine-threonine kinase/mammalian target of rapamycin signaling pathway is frequently altered in colorectal cancer (CRC). PX-866 is an oral, irreversible, pan-isoform inhibitor of PI3K. This randomized phase II study evaluated cetuximab with or without PX-866 in patients with metastatic, anti-epidermal growth factor receptor-naive, KRAS codon 12 and 13 wild-type CRC.

PATIENTS AND METHODS

Patients with metastatic CRC who had received both oxaliplatin and irinotecan were randomized (1:1) to cetuximab (400 mg/m² loading then 250 mg/m² weekly) with or without PX-866 (8 mg orally daily; arms A and B, respectively). The primary endpoint was progression-free survival (PFS). Secondary endpoints included objective response rate, overall survival (OS), toxicity, and correlation of relevant biomarkers with efficacy outcomes.

RESULTS

A total of 85 patients were enrolled. The median PFS was 59 days versus 104 days for arms A (cetuximab + PX-866) and B (cetuximab alone), respectively (P = .77). OS between the 2 arms (266 vs. 333 days for arm A vs. B) were similar (P = .83). Overall toxicity, including treatment-related toxicity, was higher in arm A compared with arm B, especially in terms of all-grade nausea (66% vs. 37%), vomiting (50% vs. 29%), diarrhea (64% vs. 18%), and rash (66% vs. 37%). Grade 3 diarrhea occurred in 19% of patients in Arm A and 0% in Arm B. PIK3CA mutations and PTEN loss by immunohistochemistry were infrequently seen.

CONCLUSION

The addition of PX-866 to cetuximab did not improve PFS, objective response rate, or OS in patients with metastatic CRC. The combination arm had greater toxicity and may have been harmful in this study.

Use of Transarterial Chemoembolization (TACE) and Sorafenib in Patients with Unresectable Hepatocellular Carcinoma: US Regional Analysis of the GIDEON Registry

BACKGROUND

Global Investigation of Therapeutic Decisions in Hepatocellular Carcinoma and of Treatment with Sorafenib (GIDEON) is a worldwide, prospective, non-interventional study to evaluate the safety of sorafenib in a variety of patient subsets.

METHODS

Eligible patients had unresectable hepatocellular carcinoma for whom the decision had been made to treat with sorafenib. Treatment strategies were instituted at the physician's discretion. Patient and disease characteristics, treatment practices, incidences of adverse events (AEs), and overall survival were collected.

RESULTS

In the United States, 563 patients were evaluable for safety. Subgroup analysis was performed for patients who underwent transarterial chemoembolization (TACE) prior to the initiation of sorafenib (group A, n=158), after the initiation of sorafenib only (group B, n=29), both (group C, n=38), or did not undergo TACE (n=318). Patient demographics were similar across the groups. In group A, 29% had Child-Pugh score B or C at diagnosis, and 19% had Barcelona Clinic Liver Cancer tumor stage C or D. In group B, 48% had Child-Pugh score B or C at study entry, and 31% had BCLC stage C or D. The majority of patients in all groups initially received full-dose sorafenib. Incidences of grade ≥3 drug-related AEs were 30%, 17%, and 16% in groups A, B, and C, respectively, and 22% in patients who did not undergo TACE. No new safety signals emerged.

CONCLUSIONS

The results from GIDEON reaffirm that sorafenib can be safely used in the context of TACE.

SPIRITT: A Randomized, Multicenter, Phase II Study of Panitumumab with FOLFIRI and Bevacizumab with FOLFIRI as Second-Line Treatment in Patients with Unresectable Wild Type KRAS Metastatic Colorectal Cancer

BACKGROUND

Second-line treatment with chemotherapy and anti-epidermal growth factor receptor or anti-vascular endothelial growth factor antibodies improves outcomes in patients with wild type Kirsten rat sarcoma viral oncogene homolog (KRAS) metastatic colorectal cancer (mCRC). The choice of biological agent in second-line mCRC remains unclear. In this randomized, phase II estimation trial, we compared FOLFIRI (irinotecan, 5-fluorouracil, and leucovorin) in combination with panitumumab or bevacizumab in patients with disease progression during oxaliplatin-based chemotherapy and bevacizumab.

PATIENTS AND METHODS

One hundred eighty-two patients were randomized to FOLFIRI with panitumumab or bevacizumab. The primary end point was progression-free survival (PFS). Secondary end points included overall survival (OS), objective response rate (ORR), and safety.

RESULTS

PFS was similar between arms, with a hazard ratio (HR) of 1.01 (95% confidence interval [CI], 0.68-1.50; P = .97). Median PFS was 7.7 months (95% CI, 5.7-11.8) in the panitumumab arm and 9.2 months (95% CI, 7.8-10.6) in the bevacizumab arm. OS was also similar between arms, with an HR of 1.06 (95% CI, 0.75-1.49; P = .75). Median OS was 18.0 months (95% CI, 13.5-21.7) in the panitumumab arm and 21.4 months (95% CI, 16.5-24.6) in the bevacizumab arm. ORR was 32% (95% CI, 23%-43%) in the panitumumab arm and 19% (95% CI, 11%-29%) in the bevacizumab arm. Skin disorders, diarrhea, hypomagnesemia, hypokalemia, dehydration, and hypotension were more frequent in the panitumumab arm. Neutropenia was more frequent in the bevacizumab-containing arm.

CONCLUSION

Panitumumab or bevacizumab with FOLFIRI as second-line treatment had efficacy similar in patients whose disease progressed during oxaliplatin-based chemotherapy with bevacizumab, with expected toxicities. The development of more accurate biomarkers might help caregivers and patients to better choose between therapies for individual patients.

Docetaxel plus oxaliplatin with or without fluorouracil or capecitabine in metastatic or locally recurrent gastric cancer: a randomized phase II study

BACKGROUND

Docetaxel/cisplatin/infusional 5-fluorouracil (5-FU; DCF) is a standard chemotherapy regimen for patients with advanced gastric cancer (GC). This phase II study evaluated docetaxel/oxaliplatin (TE), docetaxel/oxaliplatin/5-FU (TEF), and docetaxel/oxaliplatin/capecitabine (TEX) in patients with advanced GC.

PATIENTS AND METHODS

Patients with metastatic or locally recurrent gastric adenocarcinoma (including carcinoma of the gastro-oesophageal junction) were randomly assigned (1 : 1 : 1) to TE, TEF, or TEX. Each regimen was tested at two doses before full evaluation at optimized dose levels. The primary end point was progression-free survival (PFS). Overall survival (OS), tumour response, and safety were also assessed. A therapeutic index (median PFS relative to the incidence of febrile neutropenia) was calculated for each regimen and compared with DCF (historical data).

RESULTS

Overall, 248 patients were randomly assigned to receive optimized dose treatment. Median PFS was longer with TEF (7.66 [95% confidence interval (CI): 6.97-9.40] months) versus TE (4.50 [3.68-5.32] months) and TEX (5.55 [4.30-6.37] months). Median OS was 14.59 (95% CI: 11.70-21.78) months for TEF versus 8.97 (7.79-10.87) months for TE and 11.30 (8.08-14.03) months for TEX. The rate of tumour response (complete or partial) was 46.6% (95% CI 35.9-57.5) for TEF versus 23.1% (14.3-34.0) for TE and 25.6% (16.6-36.4) for TEX. The frequency and type of adverse events (AEs) were similar across the three arms. Common grade 3/4 AEs were fatigue (21%), sensory neuropathy (14%), and diarrhoea (13%). Febrile neutropenia was reported in 2% (TEF), 14% (TE), and 9% (TEX) of patients. The therapeutic index was improved with TEF versus TEX, TE, or DCF.

CONCLUSION

These results suggest that TEF is worthy of evaluation as an arm in a phase III trial or as a backbone regimen for new targeted agents in advanced GC. CLINICALTRIALS.GOV: Identifier Trial registration number: NCT00382720.

Abstract 5314: A proteomic signature predicts response to a therapeutic vaccine in pancreas cancer; analysis from the GI-4000-02 trial

Background:

We have previously reported that adjuvant treatment with a therapeutic vaccine targeting the mutated Ras oncogene product generated mutation-specific T cell responses associated with a trend toward improved survival in patients with post-operative residual disease (R1 resections) but no improvement in the overall population1. Initial analysis of 90 pretreatment plasma samples using matrix assisted laser desorption ionization time of flight (MALDI-TOF) mass spectrometry (MS) showed the potential to predict improved RFS and OS for treatment with GI-4000/gemcitabine, but not placebo/gemcitabine.

Methods:

We have developed a novel technique, combining methods used in recent advances in learning theory (‘deep learning’) with newly-refined MS techniques that allow exploration deeper into the proteome to create diagnostic tests. Using 500,000 laser shot Deep MALDI spectra2 more than 700 mass spectral features were identified. A subset of these was used to create many multivariate classifiers that were filtered for performance and combined using dropout regularization. This method allows the use of smaller training sets and so left a test set with which performance of the signature could be independently assessed. This new methodology was used to create a test (BDX-001) to identify patients likely to benefit from the addition of GI-4000 to gemcitabine.

Results:

Using BDX-001 for stratification, subjects who are BDX-001(+) demonstrated a 499 day advantage in median OS when treated with GI-4000/gemcitabine vs. placebo/gemcitabine. Additionally, these subjects demonstrated a 351 day improvement in median RFS. BDX-001 did not predict response for placebo/gemcitabine treated subjects. These results were obtained using only test set data, and although the small sample size prohibited statistical significance, it should give an unbiased test performance estimate to be validated independently.

Conclusions:

BDX-001 is a test developed using novel proteomic and learning theory methods that appears to predict treatment response to GI-4000 in resected pancreas cancer patients, potentially identifying patients with improved RFS and OS in the GI-4000/gemcitabine arm. We plan to prospectively validate BDX-001 as a companion diagnostic in a future study of GI-4000 in pancreas cancer.

References

1. Richards et al, ESMO GI. Annals of Oncology, June 2012 23 (suppl 4)

2. Duncan et al, ASMS 2013, http://asms.inmerge.com/Proceedings/2013Proceedings.aspx.

Citation Format: Donald A. Richards, Peter Muscarella, Tanios Bekaii-Saab, Lalan S. Wilfong, Vic Velanovich, Julian Raynov, Patrick J. Flynn, William E. Fisher, Samuel H. Whiting, Constana Timcheva, Tom Holmes, Claire Coeshott, Alicia Mattson, Heinrich Roder, Joanna Roder, Allen Cohn, Timothy C. Rodell. A proteomic signature predicts response to a therapeutic vaccine in pancreas cancer; analysis from the GI-4000-02 trial. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5314. doi:10.1158/1538-7445.AM2014-5314

Current practices in the management of adverse events associated with targeted therapies for advanced renal cell carcinoma: a national survey of oncologists

BACKGROUND

Oncologists treating patients with targeted therapies encounter adverse events (AEs) that pose management challenges, lead to dosing inconsistencies, and impact patient quality of life. Oncologists' practices and attitudes in the management of targeted therapy-related AEs in patients with renal cell carcinoma (RCC) are poorly understood. We sought to identify unmet needs associated with AE management and understand oncologists' treatment optimization strategies.

METHODS

A 24-item online survey was administered in August 2012 to 119 US oncologists treating patients with advanced RCC. The survey solicited responses regarding demographics, practice settings, AE management practice patterns and beliefs, treatment barriers, and patient education.

RESULTS

Respondents indicated that between 25% and 50% of patients require dose modification/discontinuation because of AEs. The greatest barrier to optimizing treatment for RCC is the unpredictability of patient responses to treatment (43%). Most respondents (78%) discuss AE management with patients, but only a minority of them proactively reach out to patients (46%). Most practitioners (70%) refer patients to nononcology specialists when faced with unfamiliar AEs, although finding interested physicians (43%) and time constraints (40%) were the most commonly cited barriers to consulting with other specialties.

CONCLUSION

Results suggest that many patients require dose modification/discontinuation because of AEs and that nononcologists are a frequently utilized resource to manage these events. There is a need for predictive drug toxicity markers to establish counseling and prevention, along with opportunities for increased education on supportive care techniques to maintain health-related quality of life and consistent dosing.

Phase I study of dasatinib in combination with capecitabine, oxaliplatin and bevacizumab followed by an expanded cohort in previously untreated metastatic colorectal cancer

PURPOSE

Dasatinib inhibits src family kinases and has anti-angiogenic properties. We conducted a phase I study of dasatinib, capecitabine, oxaliplatin, and bevacizumab (CapeOx/bevacizumab), with an expansion cohort in metastatic colorectal cancer (CRC).

METHODS

Patients were enrolled in a dose escalation cohort to establish the maximum tolerated dose (MTD) and the recommended phase II dose (RP2D). Using a "3 + 3" design, twelve patients with advanced solid tumors received dasatinib (50 mg twice daily or 70 mg daily), capecitabine (850 mg/m(2) twice daily, days 1-14), oxaliplatin (130 mg/m(2) on day 1) and bevacizumab (7.5 mg/kg on day1), every 3 weeks. Ten patients with previously untreated metastatic CRC were then enrolled in an expansion cohort. Activated src (src(act)) expression was measured by immunohistochemistry, using an antibody that selectively recognizes the active conformation of src (clone 28).

RESULTS

Twenty-two patients were enrolled between June 2009 and May 2011. Two DLTs were observed in the 50 mg bid dasatinib cohort, and one DLT was observed in the 70 mg daily dasatinib cohort. The MTD and RP2D for dasatinib was 70 mg daily. The most common treatment-related adverse events were fatigue (20; 91 %) and diarrhea (18; 82 %). Biomarker analysis of src(act) expression demonstrated that the overall response rate (ORR) was 75 % (6/8) for patients with high src(act) expression (IHC ≥ 2), compared to 0 % (0/8) for patients with low srcact expression (IHC 0 or 1); (p = 0.007).

CONCLUSIONS

The RP2D of dasatinib is 70 mg daily in combination with CapeOx/bevacizumab. High levels of srcact expression may predict those patients most likely to benefit from dasatinib.

Results of docetaxel plus oxaliplatin (DOCOX) ± cetuximab in patients with metastatic gastric and/or gastroesophageal junction adenocarcinoma: results of a randomised Phase 2 study

BACKGROUND

Patients with advanced adenocarcinoma of the gastroesophageal junction/stomach are treated by combination chemotherapy, with minimal improvements in survival. We evaluated adding cetuximab to combination chemotherapy in these patients.

METHODS

The primary objective was progression-free survival. Secondary objectives were response rate, time to response, duration of response and safety. Treatment Arm 1: docetaxel+oxaliplatin (DOCOX)=docetaxel 60 mg/m(2) plus oxaliplatin 130 mg/m(2) on Day 1 of each 21-day cycle. Arm 2: docetaxel+oxaliplatin+cetuximab (DOCOX+C)=DOCOX with C 400mg/m(2) first dose then 250 mg/m(2) weekly. The protocol was amended to allow collection of tissue to correlate responses with KRAS status.

FINDINGS

One hundred fifty patients were enrolled (75/arm). DOCOX/DOCOX+C: gastric 44%/41%, gastroesophageal junction 51%/55%, both 5%/4%. Response rate/arm: 26.5%/38.0%. Median progression-free survival: 4.7/5.1 months (95% confidence interval (CI) 3.0-5.6/4.3-5.9); 1 year survival: 39.1%/33.0%, median overall survival: 8.5/9.4 months; median duration of response: 7.3/5.6months. Grade 3-4 treatment-related adverse events (%) included neutropenia (50%/44%), febrile neutropenia (13%/19%), diarrhoea (12%/17%), fatigue (12%/17%) and leukopenia (7%/14%). Discontinuation was due to progressive disease 39/32 and adverse events 21/34. KRAS was collected on some patients 2 years into the study because of new American Society of Clinical Oncology (ASCO) findings.

INTERPRETATION

Cetuximab added to DOCOX may improve response rate minimally; there appears to be no improvement in progression-free survival, overall survival or 1-year survival. Cetuximab added to DOCOX did not produce clinically significant outcomes. Toxicities were consistent with the study drugs' known safety profiles. KRAS mutation was infrequent; no conclusions can be drawn from KRAS response data. ClinicalTrial.gov Identifier: NCT00517829.

A multicenter, phase I, dose-escalation study to assess the safety, tolerability, and pharmacokinetics of etirinotecan pegol in patients with refractory solid tumors

PURPOSE

This study was designed to establish the maximum tolerated dose (MTD) and to evaluate tolerability, pharmacokinetics, and antitumor activity of etirinotecan pegol.

EXPERIMENTAL DESIGN

Patients with refractory solid malignancies were enrolled and assigned to escalating-dose cohorts. Patients received 1 infusion of etirinotecan pegol weekly 3 times every 4 weeks (w × 3q4w), or every 14 days (q14d), or every 21 days (q21d), with MTD as the primary end point using a standard 3 + 3 design.

RESULTS

Seventy-six patients were entered onto 3 dosing schedules (58-245 mg/m(2)). The MTD was 115 mg/m(2) for the w × 3q4w schedule and 145 mg/m(2) for both the q14d and q21d schedules. Most adverse events related to study drug were gastrointestinal disorders and were more frequent at higher doses of etirinotecan pegol. Late onset diarrhea was observed in some patients, the frequency of which generally correlated with dose density. Cholinergic diarrhea commonly seen with irinotecan treatment did not occur in patients treated with etirinotecan pegol. Etirinotecan pegol administration resulted in sustained and controlled systemic exposure to SN-38, which had a mean half-life of approximately 50 days. Overall, the pharmacokinetics of etirinotecan pegol are predictable and do not require complex dosing adjustments. Confirmed partial responses were observed in 8 patients with breast, colon, lung (small and squamous cell), bladder, cervical, and neuroendocrine cancer.

CONCLUSION

Etirinotecan pegol showed substantial antitumor activity in patients with various solid tumors and a somewhat different safety profile compared with the irinotecan historical profile. The MTD recommended for phase II clinical trials is 145 mg/m(2) q14d or q21d.

A pilot trial of a combination of therapeutic vaccines (GI-4000 and GI-6207) as adjunctive therapy with first-line therapy with bevacizumab plus either FOLFOX or FOLFIRI in stage IV patients with newly diagnosed Ras-mutant positive or negative metastatic colorectal cancer

TPS3638

Background: A promising approach for the treatment of cancer is the development of vaccines that target specific tumor antigens. In the metastatic CRC patient population, targeted and active immunotherapy may inhibit cancer progression and improve survival. This trial is designed to evaluate the efficacy, immunogenicity, and safety of GI-4000 plus standard therapy in patients with metastatic colorectal cancer. GI-4000 is a proprietary immunotherapy that uses whole, heat-killed recombinant Saccharomyces cerevisiae yeast (called Tarmogens = Targeted Molecular Immunogens). GI-4000 is designed to activate a cellular immune response to target cells with activating ras mutations. Tarmogens have been shown to elicit selective killing of target cells that express a number of cancer antigens, including mutated Ras, by activation of antigenspecific T cell mediated responses. Methods: The study population consists of subjects with metastatic colorectal cancer with an activating mutation in ras. Newly diagnosed subjects receive FOLFOX (or FOLFIRI) + bevacizumab (Bev) + GI- 4000; 3 weekly injections of GI-4000 are followed by 8 cycles of Bev + FOLFOX (or FOLFIRI); day 1 and 2 every 14 days. Doses of GI-4000 are administered on day 8 of each cycle. Upon completion of chemotherapy, GI-4000 continues along with Bev maintenance every 2 weeks for up to 5 years or until subjects experience intolerance, disease recurrence, or death. If Bev is stopped, GI-4000 may continue on the same maintenance schedule alone. Subjects that have already completed standard chemotherapy (FOLFOX or FOLFIRI) may enter the study and receive Bev + GI-4000 every 2 weeks for up to 5 years. Enrollment is ongoing and will continue up to 52 subjects.

A randomized, placebo-controlled, double blind, multicenter phase II adjuvant trial of the efficacy, immunogenicity, and safety of GI-4000 plus gem versus gem alone in patients with resected pancreas cancer with activating RAS mutations/survival and immunology analysis of the R1 subgroup

e14501

Background: Patients with resected pancreas cancer treated with standard of care Gem have a median overall survival of 22 months (vs 20 months w/ observation). Activating mutations in ras occur in > 90% of pancreas cancer cases. GI-4000 is whole, heat-killed recombinant S. cerevisiae yeast that expresses mutated Ras proteins. This trial is designed to evaluate the efficacy, immunogenicity, and safety of GI-4000 plus Gem in patients with Ras mutant + resected pancreas cancer. Methods: The study enrolled 176 Ras mutant + pancreas cancer subjects post resection randomized 1:1 to GI-4000 plus Gem or placebo plus Gem (stratified by resection status; R0 or R1). Three weekly injections of GI-4000 or placebo were followed by 6 cycles of Gem 1000 mg/m2 iv (day 1, 8, 15 every 28 days). Monthly GI-4000 or placebo were administered on the Gem off-weeks and continued monthly until intolerance, disease recurrence, or death. The primary endpoint is RFS. Data for the 39 R1 subjects (GI-4000 n=19, Placebo n=20) have been unblinded and analyzed. Results: The GI-4000 group had an 11.4 week advantage in median overall survival (524 Days vs 444 Days), 16% advantage in 1 year survival (72% vs 56%), and a 4.6 week advantage in median RFS (287 Days vs 255 days). The GI-4000 group showed a significantly higher rate of mutation specific T cell response to Ras by ELISpot assay; 7/15 (47%) vs 1/12 (8%), p=0.032,with a more pronounced survival benefit in GI-4000 treated immune responders; 21.7 week advantage in median survival (596 Days vs 444 Days) compared to placebo. No significant novel toxicities have been observed to date. Conclusions: GI-4000 in combination with adjuvant Gem showed a clinically meaningful point estimate for the treatment effect on survival in R1 subjects with Ras mutant + pancreas cancer. GI-4000 was immunogenic and well tolerated. Ras specific immune response was associated with a more pronounced benefit in median survival. These data warrant further study in a definitively powered clinical trial for GI-4000 in the adjuvant setting in R1 subjects.

A phase I trial of a recombinant CEA yeast-based vaccine targeting CEA-expressing cancers

458

Background: Saccharomyces cerevisiae (yeast) has been genetically modified to express CEA protein and employed as a heat-killed immune-stimulating, vector-based vaccine. Preclinical studies have shown that yeast CEA vaccine can induce a strong CEA-specific T-cell immune response (IR) and anti-tumor activity.

Methods: Patients (Pts) were enrolled in this phase I trial at 3 dose levels: 4, 16, and 40 yeast units (each unit =107 yeast particles). The vaccine was administered equally at 4 sites subcutaneously in bilateral inguinal and anterior chest wall regions. Vaccine was administered at 2 week intervals for 3 months, then monthly. Eligible pts were required to have a serum CEA > 5 ng/ml or > 20% CEA+ positive tumor block and no autoimmune history. An expansion cohort of 10 pts was enrolled to focus on IR. Pts had re-staging scans at 3 months, then bimonthly. Peripheral blood was collected for analysis of IR including the Effector/Regulatory T-cell ratio, ELISPOT assay, changes in the myeloid-derived suppressor cells (MDSC) and natural killer cells (NK).

Results: 25 pts with progressive metastatic CEA-expressing carcinoma were enrolled; 22 had colorectal adenocarcinoma. Vaccine was well tolerated with no dose limiting toxicities. The most common adverse event was grade 1/2 injection site reaction. Overall, 7 patients had stabilization or declines in serum CEA after treatment. Of them, 5 pts (3 with colorectal cancer) had stable disease beyond 3 months and 1 is still on-going (14 +, 8, 8, 4.5 and 4 months). No anti-CEA antibodies were detected. Post vs. pre-vaccination: a) five out of 9 evaluable pts showed evidence by ELISPOT of CEA-specific T-cell IRs b) 8/16 pts had increased and 8/16 pts had decreased CD4 Effector/Treg ratio and c) 6/13 pts had increased and 2/13pts had decreased NK frequency.

Conclusions: Saccharomyces cerevisiae-CEA demonstrated an acceptable safety profile. Although this is an advanced disease population of pts which is not ideal for immune-based therapy, CEA serum stabilizations and CEA-specific IRs were seen in some pts. Randomized studies are required to determine the clinical benefit of this vaccine in a more appropriate patient population for vaccine therapy.

Panitumumab in combination with cytotoxic chemotherapy for the treatment of metastatic colorectal carcinoma

The fully human anti-epidermal growth factor receptor (EGFR) monoclonal antibody panitumumab has been shown to improve progression-free survival when administered as a monotherapy for patients with chemotherapy-refractory metastatic colorectal cancer (mCRC) and is approved in this setting. Two large randomized clinical trials have investigated panitumumab in combination with 5-fluorouracil, leucovorin, and oxaliplatin (FOLFOX) as a first-line therapy for mCRC and 5-fluorouracil, leucovorin, and irinotecan (FOLFIRI) as a second-line therapy for mCRC. In these studies, the combination of panitumumab with FOLFOX or FOLFIRI resulted in improved progression-free survival compared with FOLFOX or FOLFIRI alone. Improved tumor response was also observed with the addition of panitumumab to FOLFIRI. As in monotherapy trials, the clinical benefits associated with panitumumab treatment were confined to patients with wild-type KRAS tumors, further showing the validity of KRAS mutational status as a predictive biomarker in mCRC. In addition to KRAS mutational status, a number of other potential predictive biomarkers are currently being investigated in mCRC and may eventually help identify patients who are likely to benefit from treatment with anti-EGFR monoclonal antibodies. Toxicities observed during treatment with panitumumab combined with FOLFOX or FOLFIRI were generally manageable and commonly included skin toxicities and gastrointestinal toxicities. Because it can lead to dose delays, dose reductions, and discontinuation, physicians and patients should carefully manage skin toxicity. Overall, the results of these two studies show that panitumumab improves outcomes when added to FOLFOX or FOLFIRI among patients with mCRC with wild-type KRAS.

Safety summary of panitumumab (pmab) in combination with chemotherapy (ctx) from four clinical trials in patients (pts) with metastatic colorectal cancer (mCRC)

e15005

Background: Pmab is a fully human anti-epidermal growth factor receptor (EGFR) monoclonal antibody approved in the US and EU (wild-type KRAS) as monotherapy for pts with mCRC. Safety data from 4 studies (Siena et al ASCO 2008; Peeters et al ASCO 2008; Cohn et al ASCO 2008; Mitchell et al WORLD GI 2008) of pmab in combination with ctx are summarized. Methods: Two studies are single-arm, phase II trials and two are randomized, phase III trials with pooled, blinded safety data that include ctx-controls. All studies were multicenter. Common pt eligibility criteria included: diagnosis of mCRC with measurable disease per modified RECIST criteria, age ≥ 18 years, and adequate hematologic, renal, hepatic, and metabolic function. All studies required pts to receive FOLFOX, FOLFIRI, or irinotecan ctx in combination with pmab. Pts received pmab 6.0 mg/kg Q2W with FOLFOX Q2W or FOLFIRI Q2W, or pmab 9.0 mg/kg Q3W with irinotecan Q3W. Results from planned interim analyses are available for 3 studies, and results from the final analysis are available for one study. Results: Among the 4-study safety data, 1213 pts received pmab + ctx; 703 pts received pmab + FOLFIRI, 455 pts received pmab + FOLFOX, and 55 pts received pmab + irinotecan. Approximately 1,200 pts were enrolled in each phase III study, and data are available from 1,003 pts who received pmab + ctx and 997 pts who received ctx alone. All pts in the phase III studies, regardless of treatment group, were included in the pooled, blinded interim analysis sets monitored by the data monitoring committee for each study. Safety results for the two phase II studies of pmab + ctx and two phase III studies of pmab ± ctx are summarized (Table). Conclusions: Phase II data are consistent with expectations, and phase III trials are ongoing. A consistent safety profile was observed across studies.

[Table: see text]

[Table: see text]