The Canadian prime minister, Justin Trudeau, has said he was “saddened” by the sudden death of pharmaceutical billionaire Barry Sherman and his wife as investigators await the results of their autopsies.

Toronto police spokesman Mark Pugash said on Saturday the deaths appeared to be suspicious but offered no other details. The 75-year-old pharmaceutical magnate and his wife, Honey, 70, were found dead in their north Toronto mansion on Friday.

The deaths shocked Canadian high society and prompted Trudeau to make a statement.

Sherman founded Toronto-based Apotex Inc in 1974 with two employees and turned it into the largest Canadian-owned pharmaceutical company. Canadian Business magazine recently estimated his worth at C$4.77bn (US$3.65bn), making him the 15th richest person in the country.

The Shermans recently put up their house for sale for C$6.9m.

The Sherman family issued a statement on Saturday urging police to conduct a thorough, intensive and objective criminal investigation into their parents’ deaths and asking the media to avoid speculating on how they died.

The Shermans were among Canada’s most generous philanthropists. The couple made numerous multi-million dollar donations to hospitals, schools and charities and had buildings named in their honour.

They also hosted Trudeau for a Liberal party fundraiser in 2015. Trudeau and his wife, Sophie Gregoire Trudeau, issued a statement on Twitter. “Sophie and I are saddened by news of the sudden passing of Barry and Honey Sherman,” Trudeau said. “Our condolences to their family and friends, and to everyone touched by their vision and spirit.”

Apotex is a generic drugmaker with 11,000 employees worldwide, including more than 6,000 in Canada. The company released a statement on Saturday paying tribute to its founder, praising both his philanthropic efforts and what it described as his vision for health care.

“Patients around the world live healthier and more fulfilled lives thanks to his life’s work, and his significant impact on health care and health care sustainability will have an enduring impact for many years to come,” the statement read. “As employees, we are proud of his tremendous accomplishments, honoured to have known him, and vow to carry on with the Apotex purpose in his honour.”

Honey Sherman was a member of the board of the York University Foundation. She also served on the boards of Mount Sinai’s Women’s Auxiliary, the Simon Wiesenthal Center and the International American Joint Distribution Committee.

But Barry Sherman was not without controversy. He faced legal action from family members alleging they had been cut out of the company over the years.

“We are at a loss of words,” neighbour Sarah Alva said. “They are both the most wonderful people we knew and our hearts goes out to their families.”