The 25-year-old was named on Monday as the player who tested positive for a banned drug during the IPL held between April and June, and the Pakistan Cricket Board suspended him on Tuesday.
It is the second time in his career that Asif has tested positive for the substance, having been found with nandrolone in his system in October 2006 along with Shoaib Akhtar.
"The IPL have informed us that the B-sample of his urine could possibly be tested in the same laboratory in Switzerland on July 28," Asif's lawyer Shahid Karim told AFP.
"Asif is very keen to have his name cleared so he is anxious to go to Switzerland because he is confident to get out of this mess and play," said Karim.
Asif had a taste of trouble earlier this year when he was seized at Dubai airport while returning from the IPL in India on June 1 on charges of possessing opium.
He was detained at the airport for 19 days before the Gulf police deported him after they found the quantity of the drug "insignificant."
The fast-rising bowler was banned for one year after he first tested positive for nandrolone two years ago, while Akhtar got a two-year lay-off. Both bans were overturned on appeal.
The Pakistan Cricket Board dropped Asif from a 30-man provisional squad for September's Champions Trophy squad announced on Tuesday.
The World Anti-Doping Agency said on Friday that it was monitoring Asif's case.
"We are monitoring the case and since it is under process we would not like to comment any further. The B-sample test is a player's right," media manager Frederic Donze said.