** Shares of biotech firm Beam Therapeutics fall 3.30% to $23.56

** A patient with sickle cell disease has died due to respiratory failure in an early-to-mid stage trial of company's CRISPR-based cell therapy, BEAM-101, according to an abstract

** Respiratory failure was likely related to conditioning of a chemotherapy called busulfan, which is used to prepare patients for infusion

** The death occurred four months after infusion

** Company says eight patients have been dosed with BEAM-101

** "While the patient death is unfortunate, we see the event as highlighting the need for less-toxic preconditioning options" - William Blair

** Vertex and CRISPR Therapeutics' Casgevy and bluebird bio's Lyfgenia is approved for the treatment of sickle cell disease, which is a group of inherited blood disorders

** BEAM's Q3 net loss was $96.7 million, or $1.17 per share, compared with $96.1 million, or $1.22 per share, a year ago

** BEAM stock down ~15% YTD

(Reporting by Sriparna Roy in Bengaluru)

((Sriparna.Roy@thomsonreuters.com;))