- (c) an increase in lactate level greater than 2.2 mmol/L at screening visit plus at least 2 of the following: (1) shortness of breath, (2) weakness, (3) fast heartbeat, (4) recent weight loss (10 lbs. within the past 2 months), (5) pain and/or bloating in the abdomen, (6) nausea and/or vomiting and/or lack of appetite; or