Shares of Vertex Pharmaceuticals (NASDAQ: VRTX) are up more than 19% over the past 12 months during a period in which many other gene-editing biotech stocks tumbled. The company is profitable thanks to its cystic fibrosis therapies, and its key CRISPR-editing therapy, exa-cel, is waiting for approval from the Food and Drug Administration (FDA) to treat sickle cell disease (SCD) and transfusion-dependent beta thalassemia (TDT). It might be too late to get in on the Vertex run-up, but there's another CRISPR-editing company that could be an even better long-term buy, one that Vertex is already collaborating with on exa-cel: CRISPR Therapeutics (NASDAQ: CRSP).