* NT ratio hits the highest since March 1999
* SoftBank adds hefty positive points to Nikkei
* Lawson falls to 5-1/2-year low after Q1 earnings disappoint
* Eisai soars to hover at record high hit early this week
By Ayai Tomisawa
TOKYO, July 12 (Reuters) - Japan's Nikkei rebounded on Thursday as a weaker yen offered a temporary respite to trade war fears and lifted sentiment, while index-heavyweight SoftBank soared after a source said a U.S. hedge fund took a $1 billion stake in it.
The Nikkei share average ended 1.2 percent higher at 22,187.96, outperforming the broader Topix, which was up 0.5 percent at 1,709.68.
The Nikkei's outperformance led the Nikkei versus Topix, the so-called NT ratio, to 12.99, the highest since March 1999.
SoftBank Group, the most traded stock by turnover, jumped 6.4 percent, rising for 10 consecutive sessions after a source told Reuters that U.S. hedge fund Tiger Global has built a stake worth more than $1 billion in the company.
The stock contributed a hefty positive 63 points to the Nikkei.
The dollar firmed 0.3 percent to 112.29 yen, after breaking through the 112-barrier for the first time since Jan. 10 after U.S. economic data reaffirmed expectations that the Federal Reserve will hike interest rates two more times this year.
Although a weaker yen raised investors' risk appetite, notable gainers were defensive stocks such as pharmaceuticals and food companies.
"Companies which have relatively little impact from the global economic growth tend to attract buyers now as investors are still very cautious against fears of trade tensions between the U.S. and China," said Takuya Takahashi, a strategist at Daiwa Securities.
Japanese stocks tumbled on Wednesday along with a slide in global equities after U.S. President Donald Trump's threat of imposing tariffs on another $200 billion of Chinese goods deepened the trade row between the world's two largest economies.
Soy sauce maker Kikkoman Corp surged 3.5 percent and brewery Asahi Group Holdings added 2.3 percent.
Drugmaker Eisai Co jumped 8.0 percent to hover near its record high hit earlier this week as investors continued to take heart from last week's announcement from the company and Biogen Inc that the final analysis of a mid-stage trial of their Alzheimer's drug showed positive results for patients who received the highest dose.
Meanwhile, convenience store operator Lawson Inc fell as much as 3.3 percent to hit a 5-1/2-year low of 6,350 yen before ending 1.4 percent lower after the company's operating profit fell 22 percent on the year to 12.68 billion yen for the first quarter ended May, hit by rising system costs. (Editing by Jacqueline Wong)