The Scottish Funding Council (SFC) said it intended to "accelerate" the three-year initiative, which is running at a number of universities, including Edinburgh, Aberdeen, Dundee, Glasgow and St Andrews.
Yesterday, The Herald revealed the Access to the Professions project will see just 23 extra medical students recruited per year from the 40% most deprived areas in Scotland.
The initiative will also deliver only 29 additional lawyers, six architects, five vets and three dentists annually across Scotland from the target areas.
As a result, student body NUS Scotland and the UCU lecturers' union accused the scheme of lacking ambition.
A spokesman for the SFC last night defended the scheme, but said it would see increasing numbers in future years.
"The Access to the Professions programme addresses difficult and deep-seated issues around getting young people from poorer backgrounds into professions like law and medicine," he said.
"It's a three-year initiative across eight universities and, at its half-way point, is meeting our realistic expectations and making modest, but sustainable improvements to the number of people from deprived areas now studying for the professions.
"For us and the universities involved it's a starting point. As we move into negotiating outcome agreements for future development we'll be looking for improvements over and above the original targets."
The figures come at a difficult time for universities, which are under pressure to make courses more accessible to a wider social mix.
Last month, The Herald revealed some universities had been recruiting tiny numbers of students from the poorest backgrounds.
St Andrews University – where Prince William studied – recruited only 13 students from the most deprived backgrounds in Scotland in 2010/11.
The second-lowest proportion was at Aberdeen University, with 51, followed by Edinburgh University, with 91.
The Scottish Government has already announced plans to give universities binding targets on access, with the threat of financial penalties for those that fail.
Last week, Education Secretary Michael Russell hit out at elite Scottish universities, saying some had done "very poorly" on access.
However, universities argue they are trying hard to widen access, but low participation is a much more complex issue than simply encouraging school- leavers to apply.
St Andrews said this week that only two or three out of every 100 school-leavers from Scotland's most deprived areas were getting good enough grades to win places at elite universities.
It believes the greatest barrier for children from deprived areas is long-term poverty and a lack of educational and social support from a very early age.
After the publication of the original figures, Robin Parker, president of NUS Scotland, called for greater efforts.
He said: "With record amounts of public money going to universities it's crucial that, in return, they are pushed to do more to attract talented people from poorer backgrounds.
"The Access to the Professions scheme could be crucial in ensuring that Scotland's professions reflect Scotland's society, but we need to remember the numbers we're dealing with are tiny, especially compared with the tens of thousands of students these institutions teach each year."