Assessing real-world survival outcomes of patients (pts) with metastatic pancreatic ductal adenocarcinoma (mPDAC) treated with first-line FOLFIRINOX compared to patients from a phase 1/2 trial treated with NALIRIFOX

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Background: Treatment options remain limited for pts newly diagnosed with mPDAC. NCCN and ASCO guidelines both recommend treatment with FOLFIRINOX or gemcitabine plus nab-paclitaxel in the first line (1L) setting for pts with mPDAC and good performance status. Over 80% of randomized clinical trials (RCTs) studying treatments for mPDAC have failed to meet their primary endpoints. Recently published analyses have utilized real-world (RW) data to compare outcomes between pts enrolled in clinical trials and RW pts. This study sought to identify the eligible population of pts with mPDAC treated with FOLFIRINOX in the 1L setting who would meet RCT eligibility criteria for the phase 1/2 study (NCT02551991) evaluating NALIRIFOX for pts with previously untreated locally advanced or mPDAC, and to assess their survival outcomes. Methods: This retrospective observational study utilized the Flatiron Health EHR database. Data were analyzed for adult pts diagnosed with mPDAC between January 2016 and February 2020 who initiated treatment with FOLFIRNOX in 1L within 90 days of their diagnosis for metastatic disease. Eligibility criteria from the phase 1/2 trial were applied to select a population of RW pts who may have been eligible to enter the RCT. Pts meeting the following criteria were included: good performance scores (ECOG 0-1), adequate hematological, hepatic, and renal function, were recovered from the effects of surgery, were untreated in the year prior to initiating 1L, and had no evidence of a different cancer in the last three years. Kaplan-Meier analyses were used to assess the median overall survival (mOS) from the start of 1L FOLFIRNOX treatment. Results: Of the 1,210 pts treated with 1L FOLFIRINOX, 652 pts (53.8%) met less stringent versions of the RCT eligibility criteria in which missing values were deemed to indicate normal function/performance; 244 pts (20.2%) met the more stringent criteria and had complete data. The most restrictive selection criteria were the requirements for adequate hematological, hepatic, and renal function and having received prior therapy. The median age at treatment initiation among the 244 pts was 64 years (IQR: 58 – 70). 153 pts were male (62.7%), 158 were White (64.8%), and ECOG scores of 0 and 1 were split among the cohort 50%/50%. The mOS observed for the 244 pts was 10.1 months (95% CI: 9.1 – 11.3). The reported mOS from the phase 1/2 trial of NALIRIFOX was 12.6 months (8.7 – 18.7). Conclusions: This study demonstrates that RW data may be used to select a comparator cohort for a clinical trial. Initial estimates suggest NALIRIFOX pts from the RCT experienced longer survival than those receiving 1L FOLFIRINOX in the RW setting. Further analysis is necessary to minimize the effects of confounding and the differences in data collection between the RW and the RCT settings.

Risk of chemotherapy-induced febrile neutropenia with early discontinuation of pegfilgrastim prophylaxis: a retrospective evaluation using Medicare claims

BACKGROUND

Two recent evaluations reported that many cancer chemotherapy patients discontinue pegfilgrastim prophylaxis (PP) following the first cycle, and that these patients have a higher subsequent risk of febrile neutropenia (FN). Such evidence is based principally on the experience of younger adults with private healthcare coverage, and the generalizability of results to elderly Medicare patients is unknown.

METHODS

A matched-cohort design and data from the Medicare Claims Research Identifiable Files were employed. The source population comprised cancer patients aged ≥65 years who received chemotherapy with intermediate/high-risk for FN and first-cycle PP. From the source population, beginning with the second cycle, all patients who received PP in all previous cycles were identified. From this sub-set, patients who did not receive PP in the cycle of interest ("comparison patients") were matched to those who received PP in that cycle ("PP patients"); the same process was repeated for subsequent cycles. Odds ratios (OR) for FN (broad and narrow definitions) were estimated using generalized estimating equations.

RESULTS

Among 77,616 elderly patients in the source population, 5.3% did not receive second-cycle PP and were matched to those who did. In cycle 2, FN odds were significantly higher among comparison patients vs PP patients when employing the broad definition (OR = 1.9, p < .001) and the narrow definition (OR = 2.1, p < .001). Results for subsequent cycles (broad definition: OR = 2.0, p < .001; narrow definition: OR = 2.1, p < .001) and for the last cycle (broad definition: OR = 1.4, p = .060; narrow definition: OR = 1.7, p = .055) were largely comparable.

CONCLUSIONS

In this large-scale evaluation of elderly Medicare patients who received myelosuppressive chemotherapy and first-cycle PP in recent US clinical practice, FN risk was substantially lower among patients who continued to receive PP in subsequent cycles vs those who discontinued PP.

A within-trial cost-effectiveness analysis of panitumumab compared with bevacizumab in the first-line treatment of patients with wild-type RAS metastatic colorectal cancer in the US

AIMS

This analysis investigated the cost-effectiveness of panitumumab plus mFOLFOX6 (oxaliplatin, 5-fluorouracil, and leucovorin) compared with bevacizumab plus mFOLFOX6 in the first-line treatment of patients with wild-type RAS metastatic colorectal cancer (mCRC).

MATERIALS AND METHODS

The cost-effectiveness analysis was developed from a third-party payer perspective in the US and was implemented using a partitioned survival model with health states for first-line treatment (progression-free), disease progression with and without subsequent active treatment, and death. Survival analyses of patients with wild-type RAS mCRC from the PEAK head-to-head clinical trial of panitumumab vs bevacizumab were performed to estimate time in the model health states. Additional data from PEAK informed the amount of each drug consumed, duration of therapy, subsequent therapy use, and toxicities related to mCRC treatment. Literature and US public data sources were used to estimate unit costs associated with treatment and duration of subsequent active therapies. Utility weights were calculated from patient-level data from panitumumab trials in the first-, second-, and third-line settings. A life-time perspective was taken with future costs and outcomes discounted at 3% per annum. Scenario, one-way, and probabilistic sensitivity analyses were performed.

RESULTS

Compared with bevacizumab, the use of panitumumab resulted in an incremental cost of US $60,286, and an incremental quality-adjusted life-year (QALY) of 0.445, translating into a cost per QALY gained of US $135,391 in favor of panitumumab. Results were sensitive to wastage and dose rounding assumptions modeled.

LIMITATIONS

Progression-free and overall survival were extrapolated beyond the follow-up of the primary analysis using fitted parametric curves. Costs and quality of life were estimated from multiple and different data sources.

CONCLUSIONS

The efficacy of panitumumab in extending progression-free and overall survival and improving quality of life makes it a cost-effective option for first-line treatment of patients with wild-type RAS mCRC compared with bevacizumab.

Risk of chemotherapy-induced febrile neutropenia with same-day versus next-day pegfilgrastim prophylaxis among patients aged ≥65 years: a retrospective evaluation using Medicare claims

BACKGROUND

Two recent evaluations reported that risk of febrile neutropenia (FN) may be higher when pegfilgrastim prophylaxis (PP) is administered on same day as chemotherapy rather than per recommendation (1-3 days following chemotherapy). Such evidence is based largely on the experience of younger privately insured adults and may not be generalizable to older patients in US clinical practice.

METHODS

A retrospective cohort design and data from Medicare Claims Research Identifiable Files (January 2008-September 2015) were employed. Patients were aged ≥65 years, had breast cancer or non-Hodgkin's lymphoma, received chemotherapy with intermediate/high risk for FN, and received PP in ≥1 cycle; cycles with PP were stratified based on administration day (same-day ["Day 0"] vs. 1-3 days following chemotherapy ["Days 1-3"]) and were pooled for analyses. Adjusted odds ratios (ORs) for FN during the cycle were estimated for patients who received PP on Day 0 versus Days 1-3.

RESULTS

Study population included 65,003 patients who received PP in 261,184 cycles; in 5% of cycles, patients received PP on Day 0. Incidence proportion for FN in cycle 1 was 11.4% for Day 0 versus 8.4% for Days 1-3; adjusted OR was 1.4 (p < .001). Incidence proportion for FN when considering all cycles was 7.7% for Day 0 and 6.0% for Days 1-3; adjusted OR was 1.3 (p < .001). Adjusted ORs when considering all cycles and only inpatient FN episodes (1.3, p < .001) and the narrow definition for FN (1.5, p < .001) were similar.

CONCLUSIONS

Among Medicare patients receiving chemotherapy and PP in US clinical practice, PP was administered before the recommended timing in 5% of cycles and FN incidence was significantly higher in these cycles. Along with prior research, study findings support recently updated US practice guidelines indicating that PP should be administered the day after chemotherapy.

An assessment of KRAS, NRAS, and BRAF testing prior to 1st line of therapy among mCRC patients treated at community cancer centers in the United States

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Background: We sought to determine the proportion of patients with mCRC in the United States who were tested for KRAS, NRAS, and BRAF mutational status before any 1st line of therapy. Patient demographics that may influence testing, and the turnaround time between key events associated with biomarker testing and utilization of biomarker results were also assessed. Methods: The study utilized the Oncology Services Comprehensive Electronic Records (OSCER) 2.0 dataset, provided by Flatiron Health, which includes mCRC patients from community cancer centers across the United States. Biomarker results are recorded in the Flatiron Electronic Health Record when available. The proportion of patients tested or not tested for KRAS, NRAS, and BRAF mutational status before 1st line of therapy between 2013 and 2017 was calculated, as were the differences in the patient demographics. The median number of days between the date of tissue collection, the date the tissue was received by the laboratory, and the date the oncologist received the test results was calculated. Results: Of the 13,437 patients included in the analysis, the proportion of patients who were tested prior to 1st line of therapy was as follows: KRAS, 30.8%,; NRAS, 9.9%; BRAF, 11.5%. Age, insurance type, race, and presence of liver metastases were all statistically significant factors that influenced testing. Specifically, younger, commercially-insured, Caucasian patients, and those who had liver metastases were more likely to be tested. For KRAS testing, the median time between tissue collection and tissue received by the laboratory was 26 days. Receipt of the results by the oncologist took an additional median number of 27 days. Conclusions: This study found that the testing rate for these key mCRC biomarkers was less than 31% and that the median number of days to assess biomarker results was 26. Further studies conducted in various settings, such as academic cancer clinics, are needed to investigate this low proportion of testing and long time to assess results.

Prevalence of RAS and BRAF mutations in metastatic colorectal cancer (mCRC) patients by tumor location

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Background: There is evidence to suggest that tumor biology and pathology differ for right- and left-sided colon tumors which may affect treatment efficacy and clinical outcomes. Therefore, we conducted a systematic review and meta-analysis of the available scientific literature to summarize the prevalence of RAS and BRAF mutations by primary tumor location and to identify potential sources of heterogeneity in mutation prevalence. Methods: This study was conducted in accordance with PRISMA guidelines. Using comprehensive search strings, several medical research databases were queried and relevant variables abstracted including tumor mutation prevalence, study country, metastasis site, tissue source, study design, study dates, median age of the cohort, mutation assessment method, and length of follow-up. Results: Final abstraction was performed on 40 articles, 36 observational studies and 4 randomized trials. Most studies were from Europe (n = 16), followed by Asia (n = 11), USA, (n = 7), Australia (n = 3), and the remaining 3 were conducted in multiple countries. The proportion of males in each study ranged from 37% to 72%, and the mean age ranged from 55 to 76 years. The prevalence of all RAS mutations was significantly higher among right-sided colon tumors than left-sided colon tumors (44%, 95% Confidence Interval [CI]: 38 – 50% vs 34%, 95% CI: 29 – 38%; p = 0.009). BRAF mutation prevalence was also higher in right-sided tumors (16.1%, 95% CI: 13.1 – 19.6% vs 4.4%, 95% CI: 3.4 – 5.8%; p < 0.0001). Conclusions: This systematic review and meta-analysis found that mutation prevalence varied by primary tumor right- or left-sided location among mCRC patients. Some of this variation may be explained by study characteristics such as mutation assessment method, country and length of follow-up. Further research will help to better understand treatment and outcome implications of tumor sidedness and mutation prevalence.

RAS mutation prevalence among patients with metastatic colorectal cancer: a meta-analysis of real-world data

AIM

A confirmed wild-type RAS tumor status is commonly required for prescribing anti-EGFR treatment for metastatic colorectal cancer. This noninterventional, observational research project estimated RAS mutation prevalence from real-world sources.

MATERIALS & METHODS

Aggregate RAS mutation data were collected from 12 sources in three regions. Each source was analyzed separately; pooled prevalence estimates were then derived from meta-analyses.

RESULTS

The pooled RAS mutation prevalence from 4431 tumor samples tested for RAS mutation status was estimated to be 43.6% (95% CI: 38.8-48.5%); ranging from 33.7% (95% CI: 28.4-39.3%) to 54.1% (95% CI: 51.7-56.5%) between sources.

CONCLUSION

The RAS mutation prevalence estimates varied among sources. The reasons for this are not clear and highlight the need for further research.

Regional and practice setting differences in the management of EGFR rash among mCRC patients treated with panitumumab: Results of a national survey in the United States

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Background: Skin toxicity can be a limiting factor for the use of anti-EGFR therapies, such as panitumumab, and there are currently no standard practice guidelines for rash management in the United States (U.S.). This study aimed to evaluate if there were regional or practice setting differences in strategies used among oncologists to manage EGFR rash, including utilization of dermatologic and nursing support. Methods: 250 practicing oncologists who had treated at least three mCRC patients with panitumumab in the last year completed an online survey to report their opinions and perceptions regarding skin toxicity management strategies. Participants reported if they were affiliated with an academic/university or a community-based practice. Participants were stratified into years of practice post-fellowship ( < 10 and > 10 years) and geographic region of primary practice (West, Midwest, Northeast, Southern U.S.). Results: Oncologists surveyed did not consistently utilize dermatology support. 40% (n = 99) of practicing oncologists surveyed reported consulting a dermatologist “occasionally.” Less than 5% reported “always” consulting dermatology and 6% reported “never” utilizing dermatology support. Utilization of dermatology support varied significantly by region. In the Southern US more oncologists reported “never” consulting dermatology while in the Midwest more oncologists reported “always” utilizing dermatology support (p = 0.05). While dermatology was inconsistently utilized, oncologists frequently utilized nursing support to minimize and manage anti-EGFR skin toxicity. 73% (n = 182) of oncologists engaged nursing support to “monitor skin toxicity during treatment” and 70% (n = 175) of oncologists had nursing support to “educate on skin toxicity prior to starting treatment.” Conclusions: While nursing support is consistently utilized by oncologists in the management of EGFR rash in mCRC patients treated with panitumumab, use of dermatology support was inconsistent and varied significantly by region. This lack of consistency in toxicity management strategies highlights the need for increased physician education.

Preemptive versus reactive management of EGFR rash among mCRC patients treated with panitumumab: Results of a national survey of treating oncologists in the United States

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Background: The Skin Toxicity Evaluation Protocol with Panitumumab (STEPP) and the Japan Skin Toxicity Evaluation Protocol with Panitumumab (J-STEPP) were open-label, randomized trials that were designed to evaluate differences in preemptive versus reactive management of dermatologic toxicities associated with panitumumab among patients with mCRC. The objective of this study was to evaluate if there were differences in the knowledge and application of STEPP and J-STEPP among oncologists who self-identified as primarily managing EGFR rash preemptively or reactively. Methods: A total of 250 practicing oncologists who had treated at least three new or continuing mCRC patients with panitumumab in the last year completed an online survey to report their opinions and perceptions regarding the management strategies for mCRC patients who are treated with panitumumab. Preemptive treatment was described in the survey as beginning treatment “prior to the appearance of rash” and reactive treatment was defined as beginning treatment “after signs of rash.” Results: Of the 250 oncologists who participated in this study, n = 58 (23%) reported treating 100% of their patients preemptively and n = 38 (15%) reported treating 100% of their patients reactively. A significantly higher proportion of preemptive treaters than reactive treaters reported following the skin management strategies from STEPP or J-STEPP when managing panitumumab-related skin toxicity (31% vs 13%, p = 0.02). When asked if skin moisturizer, sunscreen, over-the-counter topical steroids, prescription topical steroids, oral antibiotics, topical antibiotics, or UV protective garments were most critical in the preemptive management of panitumumab-related skin toxicity, preemptive treaters more likely to report using oral antibiotics and reactive treaters more like to report using sunscreen (p = 0.05). Conclusions: The results of this survey highlight the wide variability in the management of EGFR-related rash among mCRC patients who are treated with panitumumab and they highlight the need for heighted education among oncologists who treat mCRC patients with panitumumab.

The treatment continuum of panitumumab, cetuximab, and bevacizumab in 1st through 3rd line by KRAS, NRAS, and BRAF mutation status among mCRC patients treated at community cancer centers in the United States

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Background: Our objective was to use real world data to evaluate of the treatment continuum of bevacizumab (Bmab), cetuximab (Cmab), panitumumab (Pmab) or no biologics across 1st, 2nd, and 3rd lines among metastatic colorectal cancer (mCRC) patients who were treated at community cancer centers in the United States. This objective was applied separately to patients with confirmed KRAS, NRAS, or BRAF wild-type (WT) or mutation (MUT) status, as well as patient who did not receive biomarker testing (UNK). Methods: This descriptive study utilized data from the Oncology Services Comprehensive Electronic Records (OSCER) database. It included 5,446 (2,064 WT, 1,807 MUT, and 1,575 UNK) patients diagnosed with mCRC between 1/1/2011 and 8/31/2015. Patients were stratified into the following mutually-exclusive categories in 1st, 2nd line, and 3rd line: Pmab only, Cmab only, Bmab only, or no biologic. Patients who survived and continued therapy were followed through the lines of therapy. Results: 23.8% of WT, 36.3% of MUT and 49.5% of UNK patients did not receive a biologic in 1st line. There were 1,003 WT patients who were treated with Bmab in 1st. Of those, n=587 (58.5%) survived and elected to continue treatment in 2nd line as follows: n=221 (37.6%) continued with Bmab, n=216 (36.8%) initiated Cmab, n=65 (11.1%) initiated Pmab, and n=85 (14.5%) received no biologic in 2nd line. Of the 221 WT patients who received Bmab in 1st and 2nd line, n=129 (58.4%) survived and initiated 3rd line treatment, of which n=20 (15.5%) received Bmab in 3rd line. There were 127/2,604 (4.9%) WT patients who were treated with Pmab in 1st line. Of those 127 patients, n=46 (36.2%) survived and elected to continue treatment in 2nd line as follows: n=11 (29.3%) continued treatment with Pmab in 2nd line, while n=14 (30.4%) initiated treatment with Bmab, n=4 (8.7%) initiated treatment with Cmab, and n=16 (36.4%) did not receive a biologic in 2nd line. Conclusions: A small proportion of patients continued treatment with the same biologic throughout subsequent lines of therapy. Many patients were not treated with a biologic in any line, even if they were confirmed WT.

A survey of medical oncologist’s opinions and perceptions regarding the management of dermatologic toxicities among mCRC patients treated with panitumumab in the United States

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Background: Dermatologic toxicity can be a limiting factor for the use of anti-EGFR therapy such as panitumumab. There is a paucity of real world data regarding the management of dermatologic toxicity among metastatic colorectal cancer (mCRC) patients treated with panitumumab in the United States (U.S.). The objective of this study is to describe oncologist's opinions regarding timing of skin rash management in relation to the initiation of treatment and perceptions regarding rash management strategies. Methods: A total of 125 oncologists were recruited from a national database via a third independent party. Eligible oncologists (i.e.: licensed and practicing oncologist who had treated at least three new or continuing mCRC patients with panitumumab in the last year) completed an online survey to report their opinions regarding the grade and type of dermatologic toxicities seen and their perceptions about management strategies for mCRC patients who are treated with panitumumab. The timing of rash management initiation was defined as pre-emptive (prior to the appearance of the rash) or reactive (after any signs of skin rash). Results: Based upon their collective experience, oncologists expect that 44% of patients will develop acneiform rash while on treatment. More than half (58%) of the oncologists reported they did not follow any practice guidelines regarding the management of dermatologic toxicities. The oncologists reported that they pre-emptively initiated the management of dermatologic toxicities in 53% of their patients. Skin moisturizer and sunscreen were reported to be the most critical preemptive management approach, while skin moisturizer, over-the-counter topical steroids, and oral antibiotics were reported to be the most critical reactive management tools for Grades 1, 2, and 3, respectively. Conclusions: Despite evidence from randomized controlled trials, a majority of oncologists do not follow guidelines for dermatologic management of EGFR-I rash. There is a clear need for better physician education and awareness of mitigation strategies for skin toxicity management in mCRC patients treated with panitumumab.

Assessment of treatment with panitumumab, cetuximab, and bevacizumab among mCRC patients with wild-type RAS or BRAF treated at community cancer centers in the United States

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Background: There is limited observational data on the use of RAS test results and treatment patterns with chemotherapy and biologics among metastatic colorectal cancer (mCRC) patients. Our objective was to use real world data to evaluate the treatment sequences of mCRC patients who have wild-type RAS (KRAS, NRAS), or BRAF and who are treated at community cancer clinics within the United States (U.S.). Methods: The sample included 536 patients in the Oncology Services Comprehensive Electronic Records (OSCER) database who were diagnosed with mCRC between 1/1/2011 and 8/31/2015. All patients had available treatment data and were confirmed to have wild-type RAS or BRAF. Patients were stratified into mutually-exclusive categories based on 1st line treatment with chemotherapy in combination with either bevacizumab (Bmab), cetuximab (Cmab), panitumumab (Pmab), a combination of Pmab, Cmab or Bmab, or no biologics. Descriptive statistics were used to summarize the data. Results: The demographics of the sample were as follows: mean age 67 years (standard deviation = 12), 55% male, 70% White, and 50% with ECOG value of zero. The use of Bmab, Cmab, or Pmab in combination with chemotherapy in 1st line treatment was follows: Bmab only (n = 270, 50%), Cmab only (n = 81, 15%), Pmab only (n = 28, 5%), and a combination of either Bmab, Cmab and/or Pmab (n = 6, 1%). No biologics were administered to 151 (28%) of the sample in 1st line. There were no statistically significant differences in age, gender, race, insurance type, region of the U.S. or ECOG status at mCRC diagnosis across the 1st line treatment categories. Of the 385 patients who received a biologic in 1st line, 94 (24%) of those who survived and selected to continue treatment received a biologic in 2nd line. Of these 94 patients, 25 (27%) of those who survived and selected to continue treatment also received a biologic in 3rd line. Conclusions: Bmab was the most commonly-used biologic among mCRC patients with wild-type RAS or BRAF in this descriptive study. Future research is needed to better understand what factors impact treatment decisions among mCRC patients.

RAS mutation prevalence among patients with metastatic colorectal cancer: A meta-analysis of real-world data

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Background: Guidelines for prescribing anti-EGFR therapy for metastatic colorectal cancer (mCRC) require prior testing to confirm RAS (exons 2, 3, 4 of KRAS and NRAS) wild-type status in Europe and the USA. There is limited published evidence reporting the prevalence of RAS mutations in patients with mCRC in a real-world setting. The aim of this study was to use data from a range of real-world sources to obtain RAS mutation prevalence estimates for different geographic regions. Methods: Aggregated RAS mutation prevalence data were collected from 13 sources, including individual pathology centers (n = 7), mCRC registries (n = 3), and Amgen-sponsored studies (n = 3). Data sources included in this study originated in Europe (n = 10), the Middle East (n = 2), and South America (n = 1). A meta-analysis of all collected data was carried out to investigate the effect of heterogeneity amongst the data sources and obtain pooled RAS prevalence estimates for each, using a mixed regression model. Results: Aggregate data from 4322 patients with mCRC were included in the pooled meta-analysis. The overall RAS mutation prevalence across all data sources was estimated to be 43.5% (95% CI: 41.5–45.5%). RAS mutation prevalence varied between data sources, ranging from low estimates of 33.7% (95% CI: 28.4–39.3%) for a Middle Eastern pathology dataset, and 34.6% (95% CI: 27.7–42.1%) for a Middle Eastern mCRC registry, to the highest estimates of 53.6% (95% CI: 43.2–63.8%) and 54.1% (95% CI: 51.7–56.5%) in two European pathology centers, in the Czech Republic and Poland, respectively. Conclusions: This is one of the first studies to carry out a large pooled analysis of RAS mutation prevalence, based on real-world data. There was a high degree of heterogeneity between the sources included, possibly due to the types of data source, patient selection criteria, geographic location, or differences in laboratory testing methods. The estimated RAS mutation prevalence reported here is lower than that in a recent pooled analysis of past clinical trials, which reported an overall prevalence of 55.5% (95% CI: 53.9–57.9%) (Peeters M, et al. Eur J Cancer 2015;51:1704–13). Further investigations are required to explain the disparity in these findings.

The prevalence RAS and BRAF mutations among patients in the Middle East and Northern Africa with metastatic colorectal cancer

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Background: Anti-EGFR therapies are recommended for metastatic colorectal cancer (mCRC) patients with confirmed wild-type RAS (exons 2, 3, 4 of KRAS and NRAS) status. There is limited published information on the prevalence of RAS mutations using real world data. The objective of this study was estimate the prevalence of RAS and BRAF mutations among patients with mCRC in the Middle East and Northern Africa (MENA) in an effort to inform the rationale for biomarker testing and treatment choice. Methods: The study included 1,669 patients from August 2013 to July 2015 with mCRC from Algeria, Bahrain, Egypt, Jordan, Kuwait, Lebanon, Libya, Morocco, Oman, Qatar, Saudi Arabia, and the United Arab Emeritus. Information on RAS mutation status was obtained from one pathology lab using High Resolution Melting Analysis. Extended RAS analysis was conducted in a subset of patients, including: overall RAS (exon 2, 3, 4 of KRAS and NRAS; n = 750), KRAS exon 2 (n = 750), KRAS exon 3 and 4 (n = 507), NRAS exon 2, 3, and 4 (n = 507), and BRAF exon 15 (n = 78). The proportion of patients with each mutation was summarized. Results: The overall RAS mutation in the full sample was 35.3% (n = 589/1669). The observed mutation for KRAS exon 2 in a subset of patients with extended RAS analysis (n = 750) was 32.4% (243/750). Out of the subjects with wild-type exon 2 (n = 507), the observed mutations rates were as follows: KRAS exon 4 (20/507 = 3.9%), KRAS exon 3 (13/507 = 2.6%), NRAS exon 2 (7/507 = 1.4%), NRAS exon 3 (6/507 = 1.2%), and NRAS exon 4 (0%). The prevalence of BRAF exon 15 was 3.8% (3/78). The most robust data on specific RAS mutations was obtained from Algeria, Egypt, and Saudi Arabia. The prevalence of KRAS exon 2 mutations in these countries was as follows: Algeria (n = 33/86 = 38.4%), Egypt (n = 83/303 = 27.4%), Saudi Arabia (n = 85/245 = 34.7%). Conclusions: To our knowledge, this is the first study to evaluate the prevalence of RAS and BRAF mutations in the Middle East using real world data. The results of this descriptive study illustrate that there is variation in the prevalence of RAS and BRAF mutations in MENA.