Question: Can RG7112 inhibit MDM2?

Context:
To assess the influence of the p53 regulatory pathway further, we studied the effect of RG7112, a small molecule MDM2 antagonist that activates p53 by preventing its interaction with MDM2, on normal megakaryocytopoiesis and platelet production.
RG7112 (2g) is the first clinical small-molecule MDM2 inhibitor designed to occupy the p53-binding pocket of MDM2.
Effect of the MDM2 antagonist RG7112 on the P53 pathway in patients with MDM2-amplified, well-differentiated or dedifferentiated liposarcoma: an exploratory proof-of-mechanism study.
We report a proof-of-mechanism study of RG7112, a small-molecule MDM2 antagonist, in patients with chemotherapy-naive primary or relapsed well-differentiated or dedifferentiated MDM2-amplified liposarcoma who were eligible for resection.
To assess the influence of the p53 regulatory pathway further, we studied the effect of RG7112, a small molecule MDM2 antagonist that activates p53 by preventing its interaction with MDM2, on normal megakaryocytopoiesis and platelet production.
Discovery of RG7112: A Small-Molecule MDM2 Inhibitor in Clinical Development.
RG7112 was the first small-molecule p53-MDM2 inhibitor in clinical development.
RG7112 binds MDM2 with high affinity (K(D) ~ 11 nmol/L), blocking its interactions with p53 in vitro.
RG7112 is a selective inhibitor of p53-MDM2 binding that frees p53 from negative control, activating the p53 pathway in cancer cells leading to cell cycle arrest and apoptosis.
The effects of RG7112 and Peg-IFNα 2a on MPN progenitor cells were dependent on blocking p53-MDM2 interactions and activating the p53 pathway, thereby increasing MPN CD34(+) cell apoptosis
The orally bioavailable MDM2 antagonist RG7112 and pegylated interferon α 2a target JAK2V617F-positive progenitor and stem cells
Initial testing of the MDM2 inhibitor RG7112 by the Pediatric Preclinical Testing Program
In this issue of Blood, Lu et al describe the cooperation between an orally bioavailable mouse double minute 2 (MDM2) antagonist (RG7112) and the pegylated interferon α (Peg-IFNα 2a) to target JAK2V617F hematopoietic progenitors and stem cells
MDM2 small-molecule antagonist RG7112 activates p53 signaling and regresses human tumors in preclinical cancer models.
Activation of p53 by the MDM2 inhibitor RG7112 impairs thrombopoiesis.
The orally bioavailable MDM2 antagonist RG7112 and pegylated interferon α 2a target JAK2V617F-positive progenitor and stem cells.
Initial testing of the MDM2 inhibitor RG7112 by the Pediatric Preclinical Testing Program.
The primary endpoint was to assess markers of RG7112-dependent MDM2 inhibition and P53 pathway activation (P53, P21, MDM2, Ki-67, macrophage inhibitory cytokine-1 [MIC-1], and apoptosis). 
RG7112 is a selective inhibitor of p53-MDM2 binding that frees p53 from negative control, activating the p53 pathway in cancer cells leading to cell cycle arrest and apoptosis. RG7112 was selected for evaluation by the Pediatric Preclinical Testing Program (PPTP) due to the relatively low incidence of p53 mutations in pediatric cancers compared with adult malignancies.
However, the hydrophobic protein-protein interaction surface represents a significant challenge for the development of small-molecule inhibitors with desirable pharmacological profiles. RG7112 was the first small-molecule p53-MDM2 inhibitor in clinical development.
Treatment with low doses of RG7112, an orally available small-molecule inhibitor of p53-MDM2, both alone and combined with pegylated interferon α 2a (Peg-IFNα 2a), significantly decreased MPN colony-forming unit-granulocyte macrophage and burst-forming unit-erythroid numbers and preferentially eliminated the total number of JAKV617F(+) MPN hematopoietic progenitor cells. The effects of RG7112 and Peg-IFNα 2a on MPN progenitor cells were dependent on blocking p53-MDM2 interactions and activating the p53 pathway, thereby increasing MPN CD34(+) cell apoptosis.
RG7112 (2g) is the first clinical small-molecule MDM2 inhibitor designed to occupy the p53-binding pocket of MDM2. In cancer cells expressing wild-type p53, RG7112 stabilizes p53 and activates the p53 pathway, leading to cell cycle arrest, apoptosis, and inhibition or regression of human tumor xenografts.

Answer: Yes, RG7112 is a small molecule MDM2 antagonist.
Exact answer: yes