advances made under the initial Note and Equity Issuance Agreement. During the fiscal years ended December 31, 2013 and 2014, $2.0 million and $6.3 million of such additional advances were made. No interest payments were made on such additional advances prior to the March 28, 2014 exchange described below.
On March 28, 2014, our Predecessors, M&F TTP Holdings LLC and certain of its affiliates and employees agreed to exchange all $116.2 million of outstanding principal and interest under the Note and Equity Issuance Agreement (including amounts advanced under the initial agreement and the 2013 Promissory Notes and amounts advanced following the December 24, 2013 amendment) for 292,722,844 Series F redeemable convertible preferred units of vTvx Holdings I and 155,219,376 Series B redeemable convertible preferred units of vTvx Holdings II. Concurrently on March 28, 2014, our Predecessors entered into an Uncommitted Advance Agreement with M&F TTP Holdings LLC and the Former Officer (as defined below). The Former Officer is no longer party to the Uncommitted Advance Agreement. Under the Uncommitted Advance Agreement, advances are made by M&F TTP Holdings LLC at its discretion periodically at our Predecessors’ request. There is no minimum or maximum amount for any advance. Advances made under the Uncommitted Advance Agreement bear interest at an annual rate of LIBOR plus 10%. Principal and interest were originally payable on demand, but on May 4, 2015, M&F TTP Holdings LLC agreed to extend the maturity date of the Uncommitted Advance Agreement to January 15, 2016. Prepayments can be made under the Uncommitted Advance Agreement without penalty. As of December 31, 2013, December 31, 2014 and March 31, 2015, $2.0 million, $27.3 million and $36.1 million, respectively, of principal was outstanding under the Uncommitted Advance Agreement. During the year ended December 31, 2014 and the three months ended March 31, 2015, our Predecessors incurred $1.1 million and $0.8 million, respectively, of interest on amounts advanced under the Uncommitted Advance Agreement.
Following completion of this offering, we will not be party to any of the above-described agreements with MacAndrews, and we will not be required to make any payments or perform any other obligations under such agreements. We will also not be able to borrow under the Uncommitted Advance Agreement.
Transactions by Our Predecessors with a Former Officer and Director
On August 9, 2013, in connection with the Rights Offering, our Predecessors issued to Dr. Mjalli (the “Former Officer”), in his capacity as Founding Scientific Investor and Chief Executive Officer of our Predecessors, 218,818,574 shares of Series F Preferred Stock (“Series F Shares”) of TransTech Pharma, Inc., which eventually was converted into vTvx Holdings I (“Predecessor vTvx Holdings I”), and 108,781,071 Series B redeemable convertible preferred units of vTvx Holdings II (“Series B Units”). In the transaction, 193,582,046 of such Series F Shares and 96,235,257 of such Series B Units vested upon the issuance thereof, such that immediately following the closing of Rights Offering, the Former Officer, together with his related entities, held a 20% fully-diluted ownership interest in each of our Predecessors. The remaining Series F Shares and Series B Units were subject to vesting under certain specified conditions. The Series F Shares became Series F convertible preferred units of vTvx Holdings I when Predecessor vTvx Holdings I became a limited liability company, vTvx Holdings I, on November 14, 2013.
On March 28, 2014, our Predecessors entered into a reaffirmation and pledge agreement (“Pledge Agreement”) with the Former Officer. Pursuant to the Pledge Agreement, the Former Officer granted a security interest to us in 18,730,276 Series F convertible preferred units of vTvx Holdings I and 9,363,128 Series B Units owned by the Former Officer (collectively, the “Pledged Units”) to secure the Former Officer’s obligations to our Predecessors under a promissory note (the “2007 Note”) issued by the Former Officer to our Predecessors. The 2007 Note matures on the earlier of March 30, 2018 or the date on which the Former Officer receives in excess of $10 million in proceeds from the sale of any shares of our Predecessors’ capital stock, PharmaCore, Inc. (“PharmaCore”) or any of our Predecessors’ or Pharmacore’s subsidiaries. Interest accrues on the 2007 Note at a rate per annum equal to the lowest rate necessary to meet the Internal Revenue Code requirements for the applicable federal rate and is payable at maturity of the 2007 Note. As of December 31, 2014, 2013 and 2012, the 2007 Note had an aggregate outstanding principal amount of $4.8 million, $4.8 million and $4.8 million, respectively, and accrued and unpaid interest of $1.8 million, $1.6 million and $1.3 million, respectively.
On December 30, 2014, the boards of directors of our Predecessors authorized a repurchase of units of our Predecessors from the Former Officer and entities related to the Former Officer. The terms of the unit