Pelham-Lane, who was a president at FTI before joining the holiday company in 2012, has founded Camarco alongside former FTI MDs Ed Gascoigne-Pees and Billy Clegg. He is continuing to work for Thomas Cook as a consultant.
Also joining them from FTI in a nine-strong team will be Louise Dolan, also a former MD, as well as former directors Georgia Mann, Hazel Stevenson and ex-FTI consultant Lindsay Thomas.
The agency will cover financial, corporate and strategic communications, with all employees given an equity stake in the business, though it is not an LLP.
Pelham-Lane, who was at FTI for 12 years, said: "It is about being with like-minded colleagues whom I’ve worked with together successfully before. We felt we had something really specific to offer and liked the idea of serving our clients in a committed way through share ownership."
Pelham-Lane declined to name the agency's clients but said they numbered more than ten and included "global and large FTSE companies" as well as an IPO.
Camarco's name appears on the intention to float document submitted yesterday by the Fair Oaks Income Fund.
Claiming it had already signed up "just under" £1m of annual retained income, Pelham-Lane added: "We are very ambitious and feel we’ve got a real opportunity in the market to grow."
A number of the departures from FTI took place last year due to contractual obligations.
A spokesman for FTI said: "We would like to wish them well with Camarco."