RBC Capital analyst Kennen MacKay attributes yesterday's late-date weakness in shares of Exelixis (EXEL) to the clinicaltrials.gov update for Roche's (RHHBY) first-line metastatic colorectal cancer maintenance study indicating that recruitment has been suspended. The study is assessing "Cotezo," a combination of Exelixis/Roche's Cotellic and Roche's Tecentriq. The analyst says his correspondence with Exelixis management highlights that this is a temporary halt on recruitment only. MacKay recommends buying Exelixis on the weakness and remains bullish on the IMblaze370 trial.