Building on the momentum of 2017, I'm pleased to report that 2018 has proven to be another year of accelerated progress and growth in the size and value of our portfolio, in our operating platform, and in capital raised and deployed.
Our gross portfolio now comprises 17 innovative young companies all working on breakthroughs in the treatment of serious diseases, led by experienced and highly expert management teams. Together these companies are conducting 26 clinical trials that are expected to read out over the next 12-18 months. The value of our holdings in these companies reached £175m at the end of 2018, driven by four successful IPOs on NASDAQ and two private financing events. These events were underpinned by strong underlying progress in the development programmes of these companies.
In building our operating platform at Arix, we have paid special attention to the industry and academic partnerships that support our activities. We are certainly proud of the strong partnerships we have built with Fosun, Ipsen, Takeda and UCB, all global leaders in the biopharma world. And our academic partnerships with Fred Hutch in Seattle and Max Planck in Germany are showing great promise in enabling us to identify and create new biotech companies from their most promising therapeutic research.
Our secondary offering in March 2018 raised additional funding for the Company, bringing the total funds raised to £250m since we formed the Company in 2016. These funds are being productively deployed into new and existing portfolio companies, including two new investments into our core portfolio and a seed investment in our discovery portfolio during the year.
Most importantly, our talented investment and corporate team are the drivers of the Company's progress and will sustain its continued growth and success in the years ahead.
The governance of Arix has continued to evolve over the past year. Sir Chris Evans played a key role with Joe Anderson and I in building the company over the last three years. With the platform and the team we now have in place, it was time to establish a clearer executive leadership model and we announced these changes in February 2019. With the continued progress we have seen over the last year I feel confident in handing this executive responsibility to Joe Anderson to lead Arix in its next phase of growth.
I'm also very grateful to Meghan FitzGerald, who played an important role on our Board in supporting the Company's early development; we wish her well in her growing US endeavours. I'd also like to welcome Art Pappas and Mark Breuer to our Board. Art brings many years of experience in the biopharma industry and in building a successful venture capital firm. Mark brings important UK board and capital markets experience after a long and successful career at JP Morgan. I look forward to working with both of them.