Vizer, who stepped-down as President of SportAccord last year, also called for the International Olympic Committee (IOC) to either take sole responsibility for anti-doping matters or to withdraw completely from having any involvement.

He was speaking in the aftermath of the World Anti-Doping Agency (WADA) data leaked by the Russian-linked Fancy Bears' hacking group which showed how dozens of top Olympians have received TUE's to take otherwise banned substances.

There is no suggestion that any of these athletes broke any anti-doping rules. 

But some have claimed that TUE's can be used as a legitimate means to hide a performance-enhancing benefit.

"I think the picture is not clear, they should bring some reforms to many areas," Vizer told insidethegames during the IJF Tokyo Grand Slam here.

"One of these was the result of the [Fancy Bears'] hacking stories. 

"Some of the athletes had benefited from the different treatments [TUEs]. 

"My opinion is that those athletes which are using different therapies should not be accepted into official competition during the effect of these products."

The most notable abuse of the TUE system came when disgraced cyclist Lance Armstrong received one justifying the use of corticosteroids after he failed four tests for the substance during the 1999 Tour de France.

Concern following the Fancy Bears' attack has centred around another cyclist in Sir Bradley Wiggins, who received permission to take corticosteroid triamcinolone acetonide due to a pollen allergy before the Tour de France in 2011 and 2012 - where he became the first British winner - and the Giro d'Italia in 2013.

There is no suggestion Sir Bradley did anything illegal, but many riders have claimed triamcinolone acetonide has significant performance-enhancing benefit as a weight loss drug.

Dutch time trialler Tom Dumoulin has claimed his use of TUE's "stinks" while 2013, 2015 and 2016 Tour de France winner and former team-mate of Sir Bradley, Chris Froome, called for an "urgent review" into the system.

Vizer believes that the current format risks harming the health of athletes by allowing them to compete when otherwise unable to.

He also thinks the current system is open to abuse 

"First of all it is not right for the health and, secondly, you could abuse the impact of the therapy," he added.

His words bear similarities to those of Russian Olympic Committee President Alexander Zhukov last month.

Zhukov described a system where athletes with "serious, at times even chronic, illnesses become Olympic champions and medalists by taking substances which are prohibited for other athletes" as "pure nonsense".

He also called for an "Expert Council" under the IOC to administer them.

All reform proposals have been firmly rejected, however, by WADA and other anti-doping bodies.

They have blamed Fancy Bears' for trying to switch the agenda away from Russian doping and claim they have tampered with evidence.

"I think the 2015 [latest] rules, when they are robustly implemented, are good and strike a right and fair balance between allowing medications for needed medical conditions and ensuring health and no performance enhancement," United States Anti-Doping Agency chief executive Travis Tygart told insidethegames last month.

Some of the athletes named by Fancy Bears' have taken TUE's in order to treat confidential medical issue which have nothing to do with sporting performance.

This comes as discussions continue over the reform of the global anti-doping system following the allegations of state-sponsored drug use across Russian sport and at events including the 2014 Winter Olympic and Paralympic Games in Sochi. 

Vizer believes the present system in which WADA's members include representatives from the IOC needs to change.

WADA President Sir Craig Reedie, elected for a fresh three-year term last month, only relinquished his IOC vice-presidency in August.

"I have mentioned before how WADA should be fully independent," Vizer told insidethegames.

"But, at the same time, I could accept that anti-doping could be managed by the IOC through a specific department. 

"It’s not appropriate for it to be related to the IOC yet not related to IOC. 

"Either [the IOC] should be independent from WADA or there should be a specific department in the IOC responsible for doping. 

"We can’t have both."

Vizer resigned from the SportAccord Presidency last year six weeks after he fiercely criticised the IOC, its President Thomas Bach and his Agenda 2020 reform process at the 2015 SportAccord Convention in Sochi. 

He described the IOC system as "expired, outdated, wrong, unfair and not at all transparent".