The first five months of 2012 saw the event agency scoop business from two pharmaceutical companies, a top UK law firm, a "major" energy firm and a partnership with the Queen Elizabeth II Conference Centre (QEIICC).
In its annual results the agency, part of Motivcom, saw turnover fall by 19% to £18m in 2011.
Fay Sharpe, Zibrant’s managing director of sales and marketing, attributed the fall to the varying requirements of clients.
She said: "While turnover is reduced this was mainly due to the fact that Zibrant acts sometimes as principal and sometimes as agent, in which case only the commission or management fee income is turnover - and this can vary from year to year subject to client requirements."
Meanwhile, operating profit fell from £2m to £912,000.