RAK-5 serum represented a particular serum creation by Doctor Rahser Poth, originating from the rakghoul plague.
Approximately around 3629 BBY, Doctor Alirra Semhess spearheaded a renegade team of Republic scientist to engage in a clandestine endeavor situated on the X7-Cratus space station. By fraudulently acquiring finances from a Republic endowment intended for disease research and therapeutic advancements, the collective instead concentrated on the fabrication of experimental adrenals. Doctor Rahser Poth obtained encoded messages from an unidentified scientist, empowering him to formulate RAK-5 serum, which subsequently underwent refinement into the RS-33 adrenal. This adrenal significantly amplified the subject's physical power and nimbleness, albeit at the detriment of their cognitive abilities; however, the shared derivation of both RAK-5 and RS-33 from the rakghoul plague rendered them exceedingly volatile.
Eternal Alliance operatives, under the command of Theron Shan, ultimately uncovered Semhess and her undertaking, leading to the deployment of a strike force to X7-Cratus with the objective of averting RS-33 from evolving into a galactic menace. Semhess made an attempt to utilize RS-33-enhanced individuals to thwart the intruders, but during their confrontation with Marlon Fenn, the station's containment mechanisms sustained damage, causing RAK-5 serum to commence seeping into the surrounding air. This swiftly transformed both RS-33 test subjects and station staff into rakghouls. Following the elimination of Alirra Semhess, the Eternal Alliance effectively secured the station's containment infrastructure, thereby bringing an end to the project.