NeoLIPA: Neoadjuvant LTX-315 in Combination with Pembrolizumab in Resectable Stage III/IV Melanoma

This is a single arm, single center, open-label phase II study to assess the effect of neoadjuvant LTX-315 in combination with pembrolizumab in patients with clinically detectable and resectable stage III-IV melanoma. Clinically detectable, fully resectable stage III or oligometastatic IV melanoma can be cured with surgery but has a very high risk of local or systemic recurrence. The risk of recurrence can be significantly reduced by adjuvant treatment with a PD-1 inhibitor. Due to the mode of action of PD-1 inhibitors (stimulating tumor reactive T cells), there is reason to believe that their effect is enhanced if given before definitive surgery and removal of tumor reactive T cells in the tumor microenvironment. Indeed, it was recently shown that the effect is greatly improved if three doses of pembrolizumab are administered prior to surgery (neoadjuvant), followed by 15 doses in the adjuvant setting, compared to giving 18 doses adjuvant. Several studies have shown that pathologic complete response (pCR) after neoadjuvant treatment correlates with recurrence-free survival (RFS). The pCR rate neoadjuvant pembrolizumab is only modest (20%), and for 8% of the patients, disease progression in the neoadjuvant phase precludes the planned surgery. LTX-315 is an oncolytic peptide generated from a host defense peptide and has both a direct killing activity and immunomodulatory properties. By inducing cell lysis and immunogenic cell death, LTX-315 can lead to increased T-cell infiltration, broadened repertoire of tumor antigens and increased diversity of T-cell clones, and thus has the potential to enhance the effect of pembrolizumab. Furthermore, the addition of LTX-315 to neoadjuvant pembrolizumab can lower risk of disease progression precluding surgery.