After five previous attempts, Adhere finally took out the largest half marathon in the world, clocking 1:10.01.
Johnson, the 2003 Cross Country Champion out-kicked Chepkemi, who won the event in 2001, to finish in 1:10:14 and claim second spot. Chepkemi completed the run in 1:10:20.
British hope Jo Pavey finished fourth in her half-marathon debut in 1:10:39.
In the men�s event, Australian Andrew Letherby finished just outside of his personal best time of 1:03.31 to finish eighth in 1:03.46.
Nearly 50,000 runners competed in the point-to-point course that started in Newcastle and finishes in South Shields, England.
On Saturday, Craig Mottram�s year ended with a flourish, setting a new world road best for 3000m at the Newcastle/Gateshead Great North road race.
As he did at the IAAF World Cup in Athens two weeks ago, Mottram once again overcame his African opposition, this time 2003 world 5000m champion Eliud Kipchoge of Kenya, to score an impressive victory.
Having beaten Ethiopian world record holder Kenesisa Bekele in Athens, Mottram once again proved too strong, racing to the line in 7:41.7 seconds, breaking a 16-year-old world best time set by Morroco's Brahim Boutayeb in 1990 at 7min 49sec.
Mottram sat on the shoulder of leader Kipchoge for the entire race, surging past him about 200 metres from the finish.
After the race, Mottram told AAP, "It was a tough race, but a great way to finish the season."
"They (Kipchoge and Bekele) are two of the best distance runners in the world at the moment, and I like to consider myself in the top five, so every time we line up it�s a great race.
"It's great for the people to see someone other than an African coming out and running well, showing the rest of the world that it can be done.
"I seem to be able to do it week in and week out now, and that's been a goal of mine, and hopefully I can continue to do it in the next few years."
In the women�s 3000m road race event, Eloise Wellings finished third in 9:11.10 to Ethiopian Meseret Defar, 8:46.90, and Russian Lilia Shobukhova, 9:07.90.
Michelle Cook � Athletics Australia Media
0430 177 668 or michelle@jumpmedia.com.au
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