** Specialty pharma firm 60 Degrees Pharmaceuticals' SXTP.O rise 27% to $2.28 in premarket trading

** Co says first patient in babesiosis trial tested negative for infection after completing treatment

** SXTP says babesiosis is a tick-borne illness; cases rising in U.S. Northeast, especially among elderly and immunosuppressed

** Trial tests malaria drug tafenoquine with standard meds in patients who failed conventional treatment

** Co says patient cleared infection by two sensitive lab tests, including an FDA-approved blood screening assay

** Tafenoquine not yet approved for babesiosis; currently used for malaria prevention

** SXTP says breakthrough therapy application for tafenoquine in babesiosis submitted to FDA on October 3

** A breakthrough therapy tag is meant to speed up development and review of drugs to treat a serious condition or unmet medical need

** Up to last close, stock down 72% YTD

(Reporting by Sahil Pandey)

((Sahil.Pandey@thomsonreuters.com))