(Adds advent of promising new drug; vaccine development campaign; economic data; business owner comment in New Jersey; N.J. and Michigan measures)
By Zachary Fagenson and Jessica Resnick-Ault
MIAMI April 29 (Reuters) - The governor of Florida, among the last to lock down his state against the U.S. coronavirus outbreak, announced on Wednesday he would permit a limited economic reopening next week while leaving restraints intact for the dense greater-Miami area.
Florida became the latest, and one of the two largest, of about a dozen states forging ahead to ease crippling restrictions on business activity without vastly expanded virus testing and other safeguards that medical experts recommend should be in place first.
"There is a light at the end of the tunnel," Governor Ron DeSantis said as he unveiled his "phase-one" plan for relaxing mandatory workplace closures and stay-at-home orders imposed four weeks ago.
Earlier in the week his counterpart in Texas, Greg Abbott, another governor closely aligned with fellow Republican President Donald Trump, announced a similar economic reopening strategy due to go into effect on Friday.
As questions lingered over when and how to loosen social-distancing rules employed as the chief weapon against a highly contagious virus with no vaccine, word emerged from Washington on Wednesday of a promising new treatment for the disease.
The U.S. government's top infectious-disease official, Dr. Anthony Fauci, said the experimental antiviral drug remdesivir, from pharmaceutical maker Gilead Sciences Inc, had proven effective in a key clinical trial.
With preliminary results showing patients recovering 31% faster with the drug than with a placebo, remdesivir will become the standard of care for treating COVID-19, the potentially deadly lung disease caused by the novel coronavirus, Fauci told reporters at the White House.
He called the development "highly significant." The U.S. Food and Drug Administration said it was in talks with Gilead about making the drug available to patients as quickly as possible.
At the same time, a senior Trump administration official confirmed reports of an escalated campaign by federal agencies to speed development of a coronavirus vaccine, with the goal of securing 100 million doses by the end of this year.
The encouraging news on the medical front contrasted with ominous new Commerce Department data showing the nation's gross domestic product contracted at an annualized rate of nearly 5% in the first quarter - its sharpest such drop since the 2007-2009 collapse - to end the longest expansion in U.S. history.
With millions of Americans out of jobs since the lockdowns went into effect and no overall federal plan beyond general guidelines issued by the White House on April 16, states and cities have come under mounting pressure to ease restrictions on as the outbreak appeared to be waning.
Public health experts have urged caution, saying that a curtailment of social distancing without large-scale virus testing or the means to trace close contacts of infected individuals could trigger a second wave of infections.
U.S. deaths from the novel coronavirus topped 60,000 on Wednesday - eclipsing the number of American lives lost during the Vietnam war - and the outbreak will soon be deadlier than any influenza season since 1967, according to a Reuters tally.
The toll has given many business owners pause about reopening, but others are ready.
"I want my business to open, but I want a healthy balance," said Holly Smith, 48, whose Designer Dawgs restaurant in Hunterdon County, New Jersey, currently offers only takeout. But she added: "I feel like we've gone about this the wrong way. We've sheltered in place too long."
New Jersey Governor Phil Murphy said he would reopen state parks and golf courses to recreation starting Saturday. In Michigan, Governor Gretchen Whitmer said she would allow construction work to resume on May 7.
Under the reopening plan in Florida, where COVID-19 has killed over 1,200 people, DeSantis said retail merchants and restaurants could open on Monday, with indoor patronage limited to 25% of capacity.
Eateries may also reopen outdoor seating with appropriate social distancing, and medical practices can resume elective surgeries and procedures. But movie theaters, bars and fitness clubs will remain shuttered for the time being, he said.
The governor left existing restrictions in place across Miami-Dade, Broward and Palm Beach counties - the three most highly populated in the state.
DeSantis had drawn criticism for waiting until April 2 to clamp down on commerce - after most other states had already done so - in part because of Florida's high proportion of elderly residents - more than a fifth are age 65 and over - who are especially vulnerable to the virus. But Florida, a key swing electoral swing state, has avoided the worst of the health crisis seen in other states such as New York and New Jersey, and DeSantis said he would take a measured approach to further reopening.
"Part of our strategy in phase one is to expand testing," DeSantis said.
But Florida Democratic Party Chair Terrie Rizzo criticized the governor's plan as lacking details on how he would quickly increase the state's virus screening, which Rizzo said ranked 22nd in COVID-19 tests per capita among all 50 U.S. states.
Other Florida Democrats questioned why the governor made no mention of the state's beleaguered unemployment system that collapsed as hundreds of thousands of residents sought benefits in the early days of the pandemic lockdown.
Reporting by Zach Fagenson in Miami; Additional reporting by Maria Caspani, Barbara Goldberg and Jessica Resnick-Ault in New York and Susan Heavey and Doina Chiacu in Washington; Writing by Sonya Hepinstall and Steve Gorman; Editing by Bill Tarrant and Cynthia Osterman