Market Leaders to Watch: iRhythm Technologies and Challenges Ahead for Collegium Pharmaceutical and FB Financial

Collegium Pharmaceutical (COLL) and FB Financial (FBK) are two stocks to sell, with COLL's subscale operations and waning returns on capital, and FBK's flat sales and below-average return on equity. iRhythm Technologies (IRTC) is a stock to watch, with its market share increasing, adjusted operating profits and efficiency rising, and free cash flow flipping to positive.