Duvelisib (IPI-145), is an orally available, small-molecule, selective dual inhibitor of phosphatidylinositol 3 kinase (PI3K) δ and γ isoforms originated by Intellikine (owned by Takeda) and developed by Infinity Pharmaceuticals. Orally administered duvelisib was rapidly absorbed, with a dose-proportional increase in exposure. The compound produced a half-life of approximately 7-12 hours, following 14 days of dosing. Duvelisib exerts profound effects on adaptive and innate immunity by inhibiting B and T cell proliferation, blocking neutrophil migration, and inhibiting basophil activation. Duvelisib blockade of PI3K-δ and PI3K-γ potentially lead to significant therapeutic effects in multiple inflammatory, autoimmune, and hematologic diseases. The molecule is in phase III development as a combination therapy for patients with haematological malignancies such as chronic lymphocytic leukemia and follicular lymphoma.

Lenalidomide (trade name Revlimid) is a derivative of thalidomide introduced in 2004. It is an immunomodulatory agent with anti-angiogenic properties. Revlimid in combination with dexamethasone is indicated for the treatment of patients with multiple myeloma (MM) who have received at least one prior therapy. Also is indicated for the treatment of patients with transfusion-dependent anemia due to low- or intermediate-1-risk myelodysplastic syndromes (MDS) associated with a deletion 5q cytogenetic abnormality with or without additional cytogenetic abnormalities. In addition, Revlimid is indicated for the treatment of patients with mantle cell lymphoma (MCL) whose disease has relapsed or progressed after two prior therapies, one of which included bortezomib. The mechanism of action of lenalidomide remains to be fully characterized. Lenalidomide inhibited the secretion of pro-inflammatory cytokines and increased the secretion of anti-inflammatory cytokines from peripheral blood mononuclear cells. Lenalidomide causes a delay in tumor growth in some in vivo nonclinical hematopoietic tumor models including multiple myeloma. Immunomodulatory properties of lenalidomide include activation of T cells and natural killer (NK) cells, increased numbers of NKT cells, and inhibition of pro-inflammatory cytokines (e.g., TNF-α and IL-6) by monocytes. In multiple myeloma cells, the combination of lenalidomide and dexamethasone synergizes the inhibition of cell proliferation and the induction of apoptosis. Recently was discovered, that protein cereblon (CRBN) is a proximate, therapeutically important molecular target of lenalidomide. Low CRBN expression was found to correlate with drug resistance in multiple myeloma (MM) cell lines and primary MM cells. One of the downstream targets of CRBN identified is interferon regulatory factor 4 (IRF4), which is critical for myeloma cell survival and is down-regulated by (immune-modulatory drugs) treatment. CRBN is also implicated in several effects of immunomodulatory drugs, such as down-regulation of tumor necrosis factor-α (TNF-α) and T cell immunomodulatory activity, demonstrating that the pleotropic actions of the immunomodulatory drugs (IMiDs) are initiated by binding to CRBN. Future dissection of CRBN downstream signaling will help to delineate the underlying mechanisms for IMiD action and eventually lead to development of new drugs with more specific anti-myeloma activities. It may also provide a biomarker to predict IMiD response and resistance. Lenalidomide also inhibited the expression of cyclooxygenase-2 (COX-2) but not COX-1 in vitro.

Dinaciclib (SCH 727965) is a small molecule inhibitor of cyclin-dependent kinases. Dinaciclib demostrates potent and selective inhibition of CDK2, CDK5, CDK1, and CDK9 activity. Dinaciclib inhibits cell cycle progression and proliferation in various tumor cell lines in vitro. Dinaciclib is a product of a drug discovery collaboration between Pharmacopeia (later Ligand Pharmaceuticals) and Schering-Plough (later Merck & Co.) that began in 1998. Dinaciclib showed promising effect in treating haematological malignancies and solid tumors.

Forodesine hydrochloride is the salt of the synthetic high-affinity transition-state analog forodesine (BCX-1777, immucillin-H), a substrate designed to mimic the properties or the geometry of the transition state of reaction. It is an anticancer drug that has been developed for the treatment of different hematologic malignancies. In December 2006, orphan designation (EU/3/06/421) was granted by the European Commission to Napp Pharmaceuticals Research Limited, United Kingdom, for forodesine hydrochloride for the treatment of acute lymphoblastic leukemia. Forodesine hydrochloride has been evaluated in Phase I/Phase II clinical trials for several cancer types including chronic lymphocytic leukemia (CLL), B-Cell acute lymphoblastic leukemia and refractory cutaneous T-cell lymphoma (CTCL). Forodesine is a potent purine nucleoside phosphorylase (PNP) inhibitor that acts by elevating plasma 2'-deoxyguanosine (dGuo) and intracellular deoxyguanosine triphosphate, which in turn affects deoxynucleotide-triphosphate pools and induces cell death by apoptosis. Forodesine in the presence of dGuo inhibited the proliferation of CEM-SS (T-acute lymphoblastic leukemia) cells with an IC50 of 0.015 uM. This inhibition by forodesine and dGuo was accompanied by a 154-fold and 8-fold elevation of endogenous dGuo triphosphate (dGTP) and deoxyadenosine triphosphate (dATP) pools, respectively. Cytotoxic activity of forodesine in the presence of dGuo was selective to T lymphocytes. It is a 10- to 100-fold more potent inhibitor of human lymphocyte proliferation than other known PNP inhibitors such as PD141955 and BCX-34.8