BRIEF-CSL Says Will Not Progress UQ-CSL V451 COVID-19 Vaccine Candidate To Phase 2/3 Clinical Trials

CSL Ltd: * UPDATE ON UQ-CSL V451 COVID-19 VACCINE-CSL.AX

* CSL WILL NOT PROGRESS VACCINE CANDIDATE TO PHASE 2/3 CLINICAL TRIALS * PHASE 1 DATA SHOWED GENERATION OF ANTIBODIES DIRECTED TOWARDS "MOLECULAR CLAMP" COMPONENT OF VACCINE

* PHASE 1 TRIAL WILL CONTINUE, WHERE FURTHER ANALYSIS OF DATA WILL SHOW HOW LONG ANTIBODIES PERSIST * BLOOD SAMPLES FROM STUDY PARTICIPANTS TESTED AFTER VACCINATION FOUND MOLECULAR CLAMP ANTIBODIES DID CAUSE FALSE POSITIVE ON RANGE OF HIV ASSAYS

* SIGNIFICANT CHANGES WOULD NEED TO BE MADE TO WELL-ESTABLISHED HIV TESTING PROCEDURES IN HEALTHCARE SETTING TO ACCOMMODATE ROLLOUT OF THE VACCINE * CSL AND AUSTRALIAN GOVERNMENT HAVE AGREED VACCINE DEVELOPMENT WILL NOT PROCEED TO PHASE 2/3 TRIALS

* DOES NOT ANTICIPATE THIS ANNOUNCEMENT WILL HAVE ANY IMPACT ON PREVIOUSLY PROVIDED FINANCIAL GUIDANCE FOR FY2021 * FOLLOWING AGREEMENT WITH AUSTRALIAN GOVERNMENT, CSL WILL NOT PROGRESS VACCINE CANDIDATE TO PHASE 2/3 CLINICAL TRIALS.