Initiation of the clin­i­cal trial triggers $50 million mile­stone pay­ment from AbbVie

South San Francisco, CA (Press Release) – Harpoon Thera­peutics, Inc. (NASDAQ: HARP), a clin­i­cal-stage immuno­therapy com­pany devel­op­ing a novel class of T cell engagers, to­day announced that the first patient has been dosed with HPN217 in a Phase 1/2 clin­i­cal trial focused on re­lapsed, re­frac­tory multiple myeloma (RRMM). HPN217 is being devel­oped under a global license and option agree­ment with AbbVie Inc. (NYSE:ABBV) and dosing of the first patient in a clin­i­cal trial has triggered a $50 million mile­stone pay­ment to Harpoon. HPN217 targets B-cell maturation an­ti­gen (BCMA), a well-validated an­ti­gen ex­pressed on malignant multiple myeloma calls. HPN217 is Harpoon’s third prod­uct can­di­date to enter the clinic and is based on Harpoon’s pro­pri­e­tary Tri-specific T cell Activating Construct (TriTAC™) plat­form designed to recruit a patient’s own immune cells to destroy tumors.

“The initiation of a clin­i­cal trial for our third prod­uct can­di­date is another sig­nif­i­cant mile­stone for Harpoon and dem­onstrates the outstanding progress we are making in ad­vanc­ing our inno­va­tive on­col­ogy pipe­line,” said Gerald McMahon, Ph.D., Pres­i­dent and CEO of Harpoon Thera­peutics. “The $50 million mile­stone pay­ment adds addi­tional fi­nan­cial resources to sup­port the HPN217 pro­gram and other de­vel­op­ment ac­­tiv­i­ties that we are conducting. The first patient was treated at Colorado Blood Cancer Institute and the Sarah Cannon Research Institute at HealthONE’s Presbyterian St. Luke’s Medical Center. We are ex­cited to be ad­vanc­ing HPN217 in the clinic and look for­ward to reporting our progress as this pro­gram matures.”

“Therapeutic choices for patients with RRMM are limited, and there is a need for addi­tional thera­peutic options,” said Natalie Sacks, M.D., Chief Medical Officer of Harpoon. “Our non-clinical data sug­gest that HPN217 has sub­stan­tial anticancer ac­­tiv­ity and provide the rationale to in­ves­ti­gate its poten­tial benefit as an effective immuno­therapy for patients with multiple myeloma.”

About the Phase 1/2 Clinical Trial for HPN217

This Phase 1/2 trial is a multi­center, open-label study designed to eval­u­ate the safety, tolerability, phar­ma­co­ki­­net­ics and ac­­tiv­ity of HPN217 in patients with RRMM. The Phase 1 portion of the trial is a dose escalation phase, with the goal of determining a rec­om­mended dose for the Phase 2 portion of the trial. HPN217 will be admin­istered to patients once weekly by in­tra­venous in­fusion. The pri­mary out­come measures will be an assess­ment of safety and tolerability, phar­ma­co­ki­­net­ics, and deter­mi­na­tion of a dose for the Phase 2 portion of the trial. Secondary end­points in­clude over­all re­sponse rate, pro­gres­sion free and over­all sur­vival, and duration of re­sponse.

The Phase 2 portion of the trial will further eval­u­ate the safety and ac­­tiv­ity of HPN217 in patients with RRMM. The trial is titled, “A Phase 1/2 open-label, multi­center, dose escalation and dose ex­pan­sion study of the safety, tolerability, and phar­ma­co­ki­­net­ics of HPN217 in patients with re­lapsed / re­frac­tory multiple myeloma. For addi­tional in­for­ma­tion about the trial, please visit www.clinicaltrials.gov using the identifier NCT04184050.

About the Agreement with AbbVie

In No­vem­ber 2019, Harpoon entered into a De­vel­op­ment and Option Agreement with AbbVie pur­su­ant to which Harpoon granted AbbVie an option to license world­wide ex­clu­sive rights to HPN217. Harpoon will be responsible for devel­op­ing HPN217 through a Phase 1/2 clin­i­cal trial. Upon exercise of the option, AbbVie would be responsible for all future clin­i­cal de­vel­op­ment, manu­fac­tur­ing and com­mer­cial­iza­tion ac­­tiv­i­ties. The licensing option for HPN217 may be exercised at any time up to the com­ple­tion of the Phase 1/2 clin­i­cal trial. The De­vel­op­ment and Option Agreement rep­re­sents a poten­tial trans­action value of up to $510 million in up­front, option and mile­stone pay­ments, plus royalties on global commercial sales. In No­vem­ber 2019, Harpoon also ex­panded its existing discovery col­lab­o­ration agree­ment by up to six addi­tional targets for a total of eight targets. AbbVie has the right to select four targets, rep­re­senting a deal trans­action value of approx­i­mately $1.2 billion plus royalties, with an option to select up to four addi­tional targets. Harpoon would be eli­gible to re­ceive up to $310 million plus royalties for each addi­tional target selected. Harpoon re­ceived an initial up­front pay­ment of $50 million in No­vem­ber 2019, with an addi­tional $50 million pay­ment due upon dosing the first patient with HPN217.

About Harpoon Thera­peutics

Harpoon Thera­peutics is a clin­i­cal-stage immuno­therapy com­pany devel­op­ing a novel class of T cell engagers that harness the power of the body’s immune sys­tem to treat patients suffer­ing from cancer and other dis­eases. T cell engagers are engi­neered pro­teins that direct a patient’s own T cells to kill target cells that express spe­cif­ic pro­teins, or an­ti­gens, carried by the target cells. Using its pro­pri­e­tary Tri-specific T cell Activating Construct (TriTAC®) plat­form, Harpoon is devel­op­ing a pipe­line of novel TriTACs initially focused on the treat­ment of solid tumors and hema­to­logic malig­nan­cies. Harpoon’s first prod­uct, HPN424, targets PSMA and is in a Phase 1 trial for metastatic castration-resistant prostate cancer. Harpoon’s sec­ond prod­uct, HPN536, targets mesothelin and is in a Phase 1/2a trial for cancers expressing mesothelin, initially focused on ovarian and pancreatic cancers. HPN217 targets BCMA and is in a Phase 1/2 trial for re­lapsed, re­frac­tory multiple myeloma. For addi­tional in­for­ma­tion about Harpoon Thera­peutics, please visit www.harpoontx.com.

Cautionary Note on Forward-looking Statements

This press release con­tains for­ward-looking state­ments within the meaning of the Private Se­cu­ri­ties Lit­i­ga­tion Reform Act of 1995. Words such as “may,” “will,” “expect,” “plan,” “anticipate,” “target,” “estimate,” “intend” and similar ex­pres­sions (as well as other words or ex­pres­sions referencing future events, con­di­tions or cir­cum­stances) are in­tended to identify for­ward-looking state­ments. These for­ward-looking state­ments are based on Harpoon Thera­peutics’ ex­pec­ta­tions and assump­tions as of the date of this press release. Each of these for­ward-looking state­ments in­volve­s risks and un­cer­tainties that could cause Harpoon Thera­peutics’ clin­i­cal de­vel­op­ment pro­grams, future results or per­for­mance to differ sig­nif­i­cantly from those ex­pressed or im­plied by the for­ward-looking state­ments. Forward-looking state­ments con­tained in this press release in­clude, but are not limited to, state­ments about the antic­i­pated safety, efficacy and patient man­agement benefits of HPN217 for the treat­ment of patients with re­lapsed / re­frac­tory multiple myeloma, antic­i­pated ad­van­tages the TriTAC plat­form may have over other ther­a­pies, the progress, timing, scope and results of clin­i­cal trials, the association of data with treat­ment out­comes and the timing and like­li­hood of de­vel­op­ment mile­stones for prod­uct can­di­dates. Many factors may cause dif­fer­ences be­tween current ex­pec­ta­tions and actual results, in­clud­ing unexpected safety or efficacy data observed during clin­i­cal studies, clin­i­cal trial site activation or en­roll­ment rates that are lower than ex­pec­ted, changes in ex­pec­ted or existing com­pe­ti­tion, changes in the regu­la­tory en­viron­ment, the un­cer­tainties and timing of the regu­la­tory ap­­prov­al process, and unexpected lit­i­ga­tion or other disputes. Other factors that may cause Harpoon Thera­peutics’ actual results to differ from those ex­pressed or im­plied in the for­ward-looking state­ments in this press release are discussed in Harpoon Thera­peutics’ filings with the U.S. Se­cu­ri­ties and Ex­change Com­mis­sion, in­clud­ing the “Risk Factors” sections con­tained therein. Except as required by law, Harpoon Thera­peutics assumes no obli­ga­tion to update any for­ward-looking state­ments con­tained herein to reflect any change in ex­pec­ta­tions, even as new in­for­ma­tion be­comes avail­able.

Source: Harpoon Thera­peutics.