The government has played down the news that no student taking the higher level Diploma managed to get an A or A*.
Some 212 pupils who took the pilot Diploma course this year received their results on Thursday.
Of these, 91 took the higher level Diploma, which counts for seven A* to C-grade GCSEs.
While no students achieved A or A* grades, 19.8 per cent received a B and 73.6 per cent got at least a C.
And 26.4 per cent failed because unlike a GCSE, which is scored from A*-G, diploma students can only achieve grades A*-C.
The system had been heralded by schools secretary Ed Balls as the future for school qualifications.
He previously suggested that Diplomas could replace the A-level as the "qualification of choice".
He told an audience at the CBI conference in London two years ago: "If Diplomas are successfully introduced and are delivering the mix that employers and universities value, they could be come the qualification of choice for young people."
But following the latest results, junior schools minister Vernon Coaker said only: "Completing a full Diploma programme of study within one year is ambitious and those learners who have achieved this year are to be congratulated."
A further 121 pupils sat the foundation Diploma course, which counts for five GCSEs at grades D to G.
Head of the Edexcel exam board Jerry Jarvis sought to explain why the results were disappointing.
"It would appear that the reason for students who attempted the Diploma but did not get all the components was dominated, certainly, by functional skills," he said.
"Attainment of all three functional skills has been a hurdle."
The Department for Children, Schools and Families released data which showed that around 600 students tried to complete the Diploma course in one year.
According to their figures, only 178 of these students were given a grade, while 34 got a U and the rest were not graded.
