
The last peak-time showing of Brookside will be on November 21 at 8.30pm. From November 30 the show will be broadcast as a single, 90-minute special on Saturday afternoons.
The shake-up follows chief executive Mark Thompson's plans to revitalise the channel's programming schedule as outlined in his speech at the Edinburgh Festival in August.
Contractually C4 is committed to showing the programme until the end of 2003, but no decision has been made beyond that.
In as statement Thompson, said: "Brookside has been a brilliant programme for Channel 4 as well as the most ground-breaking and influential soap of the past two decades. It remains a high quality drama, which is still enjoyed by many viewers."
"But peak-time has changed radically across British TV and is no longer an environment in which Brookside can thrive. We want to explore new ideas in peak, while still giving Brookside regulars a chance to enjoy the show over the next year."
Brookside is made for Channel 4 by Phil Redmond and Mersey Television and it has made stars out of Anna Friel, Amanda Burton, Ricky Tomlinson and Sue Johnston.
Redmond said: "I accept that 2003 is likely to be the last year of Brookside in its present form. Mersey Television and Channel 4 will review the programme’s future early next year."
The overhaul at C4 sees teen-soap Hollyoaks increase its frequency to five nights a week from four in the new year.
Drama series already in production for 2003 include a third series of Teachers, a new hard-edged prison drama called Buried, and the 10-part Twenty Things To Do Before You’re Thirty and 40, written by Bryan Elsley and starring Eddie Izzard, Joanne Whalley and Hugo Speer.
The future of Richard and Judy, and breakfast show RI:SE are also believed to be under review, as they have failed to live up to expectations and achieve the audiences that C4 was hoping for.
Daytime king and queen Richard Madeley and Judy Finnigan have failed to repeat the success they enjoyed at ITV when they presented This Morning, following a £2m a year deal with Channel 4 to present its early evening show.
The show draws an average audience of 1.6m, compared with the 3m peak they achieved at ITV.
RI:SE, the replacement for the Big Breakfast, has failed to shine since it launched in April. The show has drawn a high of 458,000 viewers in July and a low of 178,300 in June.
Worryingly, its predecessor was axed when ratings fell to a low of 300,000 from a high of 1.5m. RI:SE is consistently beaten by Channel 5's early morning cartoons, which attract 300,000 viewers.
Meanwhile, speculation is mounting that two Channel 4 executives have expressed an interest in the vacant chief executive job at Channel 5. Channel 4 director of programmes Tim Gardam is one and David Brooks, director of strategy, is another. Both have denied they are going for the job.
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