Background: Patients with advanced colorectal cancer (CRC) are commonly administered chemotherapy by 5-Fluorouracil in various combinations with leucovorin, oxaliplatin and irinotecan. Metastatic CRCs are additionally eligible for targeted anti-VEGF treatment and anti-EGFR therapy if the tumor is KRASwt. Unfortunately, the response rates are low and novel drugs are needed. Cell lines have successfully been employed to predict drug response and several studies have demonstrated that CRC cell lines recapitulate the genetic variation among primary CRCs. Methods: We performed a high-throughput drug screen (n= 461) of 36 CRC cell lines. A multiplexed assay assessed drug effects on cell viability and cytotoxicity from a five-fold concentration range. Sensitivities were measured by calculating a drug sensitivity score for each drug using a validated algorithm that estimates the relative inhibition by normalization against the top asymptote of the drug concentration curve. By integrating drug sensitivity data with in-house datasets on DNA copy number, gene expression and deep DNA sequencing, we aimed to validate genetically indicated drug sensitivities and identify novel drug sensitivities among subsets of CRCs. Results: Pharmacological relationships for molecular subgroups of CRC were revealed by clustering analyses, outlier analysis and t-tests of the drug sensitivity scores. We found robust correlations between BRAF-mutation status and response to BRAF-inhibitors, and lack of response to Fluorouracil and its prodrug Capecitabine for cell lines with microsatelite instability. These cell lines were sensitive to Topoisomerase I-inhibitors, such as Irinotecan, Valrubicin and Idarubicin. Cell lines with TP53wt were sensitive to the TP53-MDM2 interaction inhibitor Nutlin-3. We additionally identified a more potent novel TP53-MDM2 interaction inhibitor. Pharmacologic correlations for drug classes such as MEK-, EGFR-, Aurora A/B-, PI3K/AKT-, HSP90 and IGF1R-inhibitors were also found. Conclusions: A comprehensive drug screen of 36 CRC cell lines confirms pharmacogenomic relationships and reveals novel potentially relevant therapies for CRC.