Stebbing, a high-profile cancer surgeon who has been BB’s chair since it joined the stock exchange in 2016, will remain on the board as a non-executive director.
“After a few years helping to build up the trust to the excellent Company it is today and after much deliberation, I feel it is the right time for me to step aside as chairman but I am keen to remain involved in this exciting project,” said Stebbing.
His successor, Grewal, has been a non-executive director at BB since the end of 2016. The Cambridge graduate is a portfolio manager at Trium Capital and also sits on the board of Tissue Regenix Group PLC (LON:TRX).
He will take up his new role as BB’s chairman with immediate effect.
“Justin's invaluable input has helped grow the Company into something which invests meaningfully in innovative companies that are improving healthcare for patients globally,” said Grewal.
“Although he is stepping down as chairman, we are delighted that he will continue to serve the company as a non-executive director.”
BB Healthcare made the announcement as it reported its results for the half year ended May.
The net asset value (NAV) per ordinary share rose to 132.3p from 122.1p last year and its share price stood at 134.5p, up from 121.5p a year ago.
The share price total return was down 2.5% and the NAV total return dropped 3.2% but that was better than the 4.5% negative return for the MSCI World Healthcare Index.
"Whilst the absolute return is negative, it is arguable that the company's returns should be viewed against a background of volatile market conditions and they compare favourably to other listed peers in the healthcare sector," the firm said.
"Despite the wider market volatility, the company's share price has shown a lower level of deviation from the underlying NAV."
The company declared an interim dividend of 2.425p per shares.
BB Healthcare were down 0.7% to 142.5p in early deals on Wednesday.