Cross posted from Nature Medicine’s Spoonful of Medicine blog.

The announcement on Tuesday that Seth Berkley will be taking the job of chief executive officer of the GAVI Alliance in August pulsed though the global health community. The GAVI Alliance, which faces a coming hurdle in raising the estimated $3.7 billion it needs to continue its global immunization efforts, has been without a CEO since the departure of Julian Lob-Levyt in October.

Berkley began developing the International AIDS Vaccine Initiative (IAVI) in 1994, and he has led the charge at the New York-based organization since it formally launched two years later. He’s seen the field through highs and lows, ranging from the disappointing STEP trial in 2007 to the more recent good news from the so-called RV 144 trial in Thailand, which in 2009 reported as much as 30% protection against HIV.

Nature Medicine caught up with Berkley today to hear what he has learned in his quest for a protective shot to stop the spread of HIV. What follows is a condensed version of the conversation:

This must be a bittersweet moment for you. What are your thoughts on how the HIV vaccine field has evolved?

I would say that I’m very excited about the field now, not only because of the Thai results, but we’ve [also] made enormous advances in the area of neutralizing antibodies over the last 18 months and now have many, many targets on the virus as well as antibodies that neutralize all of the strains at incredibly low doses. The science is in fabulous shape.

Looking back, how would you guess that we should start thinking about combining approaches to HIV vaccination?

At the end of the day, what you want is a vaccine that provides both neutralizing antibodies and cellular immunity. That’s what the best of other vaccines do, and certainly given the variability of this organism if you could only have one of those you’d probably want neutralizing antibodies because of the fact that neutralizing antibodies can block acquisition. Of course, to do good neutralizing antibodies you have to have T helper cells. But in terms of having an ability that if some of the virus was to get through, to have a way to mop that up with cell-mediated immunity would be important.

Read the rest of the interview here.