When asked about hydroxychloroquine, Ghaly said, "Today it's becoming more clear that it really isn't a drug that is the first line or second line in treating COVID patients."
"I would say now that it isn't an important tool in the treatment of COVID-19," he added.
The anti-malaria drug has been repeatedly touted by President Donald Trump as an effective treatment. His son, Donald Trump Jr., had his Twitter account suspended for tweeting a video about the drug that the social media site said violates its guidelines on misinformation.
The U.S. Food and Drug Administration says hydroxychloroquine is not effective in treating COVID-19.
L.A. County reports additional 51 deaths due coronavirus, 2,708 new cases
"I go along with the FDA," said Dr. Anthony Fauci on Good Morning America on Tuesday. "The overwhelming prevailing clinical trials that have looked at the efficacy of hydroxychloroquine have indicated that it is not effective in coronavirus disease."
On the other hand, remdesivir appears to be a somewhat effective therapeutic, Ghaly said, in reducing the length and severity of hospital stays. Remdesivir is an anti-viral drug.
He said the drug was being distributed to hospitals around the state and has had "some impact" on treating coronavirus. He said more California-specific data was still needed.
As of Tuesday, there were 466,550 COVID-19 cases reported in the state. California has seen an average of about 9,000 new cases a day for the past two weeks.
The positivity rate, which shows what percent of people taking COVID-19 tests turn back a positive result, has been hovering at around 7% for weeks.
But while the positivity and hospitalization numbers have become more stable statewide, Gov. Gavin Newsom says certain regions and sectors of our economy are disproportionately impacted by the transmission of the virus.
As a result, Newsom announced a $52 million investment in central California to improve isolation protocols, testing and to help health care workers. The money is part of a $499 million grant the state received from the CDC.
KGO-TV contributed to this report.
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