In clinical trials, additional serious side effects in patients receiving Avastin with chemotherapy included non-GI fistula formation, strokes or heart problems (blood clots), hypertensive crisis (severe hypertension), reversible posterior leukoencephalopathy syndrome (nervous system and vision disturbances), neutropenia (a reduced white blood cell count that may increase the chance of infection),
nephrotic syndrome (a sign of severe kidney malfunction), and congestive heart failure.