Antonio Gualberto
Analyst · STB Leerink. Your line is now open
Thank you, Troy. Among the compelling features of the tipifarnib problem when we licensed it from Johnson were the signs of durable anti-tumor activity upsurge across multiple hematologic indications as well as certain solid tumors. Despite this evidence of activity, the mechanism of action of farnesyltransferase inhibitors has remained elusive for decades. The data we had generated in HRAS-mutant HNSCC provided the strong evidence of activity in tumors driven by these exclusively farnesylated oncogene. However, many of the other tumors in which evidence of activity have been reported, such as lymphomas, myeloid leukemia, pancreatic cancer or breast cancer do not typically correlate as that mutations. In December 2018, at the American Society of Hematology Annual Meeting, we reported primary data from our phase two trial of tipifarnib, a later stage peripheral T-cell lymphoma. The data show a significant association between CXCL12 expression and clinical benefit as well as clinical proof of concept angioimmunoblastic T-cell lymphoma, an aggressive form of PTCL, often characterized by high levels of CXCL12 expression. At the same time, we reported results from an ancillary, non-clinical study which indicated that high CXCL12 expression is, in fact, a negative prognostic factor for a standard of care PTCL therapy. We also showed that tipifarnib can now regulate CXCL12 secretion in models of bone marrow stroma. The preliminary results reported attached validated our observation that the CXCL12 pathway is a therapeutic target of tipifarnib and provided a potential path to expand the development of tipifarnib well beyond HRAS-mutant solid tumors by using CXCL12 related biomarker to enrich for patients most likely to benefit from tipifarnib treatment. Importantly, CXCL12 and its receptors are known to contribute to metastasis. An elevated CXCL12 expression is known to be a poor prognostic factor in patients with certain tumors, including pancreatic cancer. We are increasingly encouraged by our growing body of CXCL12 related data. An outstanding question, however, still remains. What are the molecular mechanisms that relate the inhibition of the farnesyltransferase and sign with the observed anti-tumor activity of tipifarnib in patients with high CXCL12 expression? As previously stated, despite the fact of a number of large pharma companies and academic investigator, have work on farnesyltransferase inhibition for many years. Not the mechanism of such in the clinic have been defined. Last month, at the American Association for Cancer Research Annual Meeting, we reported new findings suggesting that the gene expression of the exclusively farnesyl prodding [indiscernible] is strongly associated with CXCL12 expression in bone marrow stroma. We believe this funding may help us identify a molecular mechanism connecting farnesyltransferase inhibition with a targeting of the CXCL12 pathway by tipifarnib. Individual analysis of a subset of patients from a previously conducted phase 2 trial in the lab refer to lymphoma identified CXCL12 expression as a potential buyer market of clinical benefit from tipifarnib in patients with diffuse large B-cell lymphoma as well as mycosis fungoides, the most common form of cutaneous T-cell lymphoma. These findings provide further evidence supporting the inhibition of the CXCL12 pathway to make it in for such immediate in the activity of tipifarnib in the clinic We believe that CXCL12 pathway biomarkers provide the common mechanistic basis to enrich for political benefit across multiple hematological and solid tumors indications. Now we look forward to providing additional data from the two cohorts in our ongoing phase two trial of tipifarnib in light estate PPPCO, including original response data from the AITL cohort and original data from the CXCL12 positive PTCL cohort. I am pleased to report that this data have been accepted for all our presentation. At birth, there would be a hematological association. And while congress and the international conference of malignant lymphoma, both in June. Meanwhile, we continue our efforts to further elucidate the biology of farnesyltransferase and the specific molecular mechanism for action of tipifarnib, including the identification of genetic mutations potentially associated with a limited CXCL12 expression. And we expect more to say on that either at ICML next month as well. With that, I will now turn the call back over to Troy.