The 800m world and Olympic champion will not race at the World Athletics Championships in Doha because of new rules governing testosterone levels in female athletes.

Semenya has said she will continue her appeal against the governing body's decision.

Coe said the rules ensured a "level playing field" for all athletes.

"I hope within the regulations that we've set that she's able to continue in track and field. And that's why we've done it," Coe told BBC Sport.

"We haven't set those regulations to exclude people. They are actually there to allow us to maintain the presence of those athletes with that condition at international level."

Asked whether he wanted to see Semenya return to race in the 800m, he said: "Yes, within those regulations of course".

The new rules from the sport's world governing body, the International Association of Athletics Federations, state that athletes with differences of sexual development (DSD) must take medication to reduce their levels of testosterone - a hormone that increases muscle mass - in order to compete in track events from 400m to the mile, or change to another distance.

Semenya had been able to race earlier in the season while awaiting the decision of a Swiss court, having previously lost an appeal to the Court of Arbitration for Sport.

But the Swiss Federal Supreme Court upheld the original decision in May, meaning Semenya cannot compete in the 800m without taking medication.

"It is a very, very important concept and we do need to make sure that athletes entering an event or a discipline feel that they've got the same chance, the same career opportunities as anyone entering," Coe added.

'Alarm bells should be ringing if you miss a test'

One athlete due to compete at the World Championships, which start on Friday, is American sprinter Christian Coleman, who had been charged with missing three drugs tests and was facing an automatic one-year ban.

But the US Anti-Doping Agency (Usada) withdrew the charge earlier this month after receiving guidance from the World Anti-Doping Agency (Wada).

Coe says he is "pleased" the agencies are now looking to clarify the rules that led to the charge against 23-year-old Coleman.

"It is important that we've got regulations that are clear and without ambiguity and the reputation of athletes is very serious," he added.

Under the 'whereabouts' system, athletes must let officials know where they will be for one hour every day as well as details of overnight accommodation and training.

Failure to do so three times in a 12-month period could lead to a rule violation under the Wada code.

Coleman, who ran a world-leading time of 9.81 seconds in the 100m at the Diamond League in Stanford, California in June, defended himself after being charged, saying he has "never failed a drug test and never will".

Usada initially claimed he had missed three tests in a 12-month period - but a "filing failure" meant the original dates reported were amended, and Coleman was cleared.

"I think as most athletes would accept, if you miss one, the alarm bells should be ringing and you just don't want to get careless about it," Coe said.

Coleman is set to line up in Doha against fellow American and defending champion Justin Gatlin - who has served two doping bans.

Coe says these cases should not affect faith in sprinting.

"Our history in some areas has been a sad one, it's caused all of us who love the sport personal anguish," he said.

"My responsibilities now are to make sure we have systems in place, that those systems are far securer and the athletes are under a much stricter regime than they've ever been.

"Crucially, the athletes are much more confident about the system they are in."

Transgender athletes - 'the next big issue'

Earlier this year, ex-swimmer Sharron Davies and former athletes Dame Kelly Holmes and Paula Radcliffe wrote to the International Olympic Committee (IOC) asking for more research on the "residual benefits" of being a transgender athlete.

Davies later said it will take female athletes "being thrown under the bus" at Tokyo 2020 before changes are made to transgender rules.

Under IOC guidelines, athletes who have transitioned from male to female are required to have kept their levels of testosterone below a certain level for at least 12 months.

"We all know that the next big issue is going to be transgender and that's really important," said Coe.

"We will need to have a system, a structure that is able to address that. It will be discussed at our council meeting in Doha.

"We're not hiding from these issues, we think we are a sport uniquely placed to help address these challenges."

Asked if he could see a transgender woman winning medals at a World Championships, he said: "I'm not going to speculate on that but I think, for me, it's pretty clear we will need some guiding regulations around that if that is to take place."