On December 8, 2020 Actinium Pharmaceuticals, Inc. (NYSE AMERICAN: ATNM) ("Actinium" or the "Company") reported that first-in-human data from the first dose cohort of the Phase 1 portion of the Actimab-A venetoclax Phase 1/2 combination trial in patients with relapsed or refractory Acute Myeloid Leukemia (AML) were presented at the 62nd American Society of Hematology (ASH) (Free ASH Whitepaper) annual meeting (Press release, Actinium Pharmaceuticals, DEC 8, 2020, View Source [SID1234572450]). The poster presentation highlighted results from the first three patients treated with the initial subtherapeutic dose level of 0.5 μCi/kg of Actimab-A and venetoclax.

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The enrolled patients had a median of 2 prior therapies (range 2-3) and a median bone marrow blast percentage of 30% (range 20 – >60). All 3 patients had poor risk disease with adverse cytogenetics, and each patient had an additional high-risk marker (FLT3-ITD+, antecedent JAK2+ myelofibrosis, or TP53 mutation). One patient who had multiple genetic mutations including IDH2, RUNX1, TP53 and others, achieved a complete remission with incomplete blood count recovery (CRi) after the first cycle of Actimab-A and venetoclax. Next generation sequencing at the end of the first cycle showed that patient was negative for the known IDH2 and RUNX1 mutations. This patient has continued treatment receiving the second cycle and their bone marrow remains normocellular with no excess blasts. In addition, another patient achieved a partial response after one cycle of Actimab-A and venetoclax. There were no Actimab-A related dose limiting toxicities or nonhematologic Grade 3 or greater related AEs reported in the first cohort. The trial has advanced to the second dose cohort of 1.0 μCi/kg of Actimab-A and venetoclax with patient enrollment ongoing.

Sandesh Seth, Actinium’s Chairman and Chief Executive Officer, commented, "This ASH (Free ASH Whitepaper) meeting, we are excited to highlight the promising data emerging from both our combination trials with Actimab-A in the R/R AML setting, namely the Actimab-A venetoclax and Actimab-A CLAG-M trials. Particularly compelling is the complete response reported in a patient with complex mutations like TP53 with Actimab-A and venetoclax and the high MRD negativity rate with Actimab-A and CLAG-M. The results clearly demonstrate that a superior clinical effect without adding meaningful toxicity is achievable using Ac-225 ARC’s to precisely deliver powerful internal radiation and elicit a potentiating and synergistic treatment effect with chemotherapy and targeted agents. With this clinical validation in hand, we look forward to expanding our ARC combinations with other therapeutic modalities in AML and into additional indications to further establish our leadership position in the field by leveraging our enhanced R&D capabilities including new research facilities and key hires."

Dr. Mark Berger, Actinium’s Chief Medical Officer, said, "We were thrilled to report a complete response in the Actimab-A venetoclax combination trial, in addition to the partial response previously highlighted in the abstract. Both responses occurred after just one cycle of a subtherapeutic dose of Actimab-A. These initial results, the one complete response and safety profile to date, support the potential mechanistic synergy of Actimab-A with venetoclax. As a single agent, venetoclax has produced low response rates of 19% in patients with R/R AML1 so we are pleased with the results seen in our first dose cohort. In addition, the clinical data from Actimab-A and Iomab-B presented at this year’s ASH (Free ASH Whitepaper) demonstrates our strong commitment to addressing the unmet needs of patients with R/R AML with our ARCs as best in class therapeutics, bridge to transplant and targeted conditioning for potentially curable bone marrow transplant. With this in mind, we look forward to guidance on Iomab-B expected from the ad-hoc DMC meeting before year-end."

This Phase 1/2 trial is a multicenter, open label trial of Actimab-A (lintuzumab-Ac225) added to venetoclax for patients with CD33 positive R/R AML. A Phase 2 trial studying Actimab-A as a single agent produced a 69% overall response rate in older unfit patients with newly diagnosed AML. In a poster presentation at the American Association of Cancer Research (AACR) (Free AACR Whitepaper) Annual Meeting 2019, Actimab-A was shown to be synergistic with venetoclax in venetoclax resistant cell lines, by depleting MCL-1, a protein shown to mediate resistance to venetoclax. Further, the induction of direct AML cell death via double-stranded DNA breaks by Actimab-A provides a second mechanism for enhancing synergistic potency with venetoclax. Venetoclax is a B-Cell Lymphoma 2 (BCL-2) inhibitor that is jointly developed and marketed by AbbVie and Genentech and is approved for patients with AML, Chronic Lymphocytic Leukemia (CLL), and Small Lymphocytic Leukemia (SLL). Despite its approval in AML, venetoclax has produced low response rates of 19% as a single agent in R/R AML.1 This is due in part to the type of AML, risk factors, and cytogenetics of this patient population. The Phase 2 trial results, together with a synergistic mechanism of action with venetoclax demonstrated in pre-clinical studies, are driving this combination trial with an initial focus on the high unmet needs of R/R patients including those who have relapsed or do not respond to treatment with venetoclax based regimens.

1 Aldosset al. Efficacy of the combination of venetoclax and hypomethylating agents in relapsed/refractory acute myeloid leukemia. Haematologica2018.1888094.

About Actinium’s CD33 Program

Actinium’s CD33 program is evaluating the clinical utility of Actimab-A, an ARC comprised of the anti-CD33 mAb lintuzumab linked to the potent alpha-emitting radioisotope Actinium-225 or Ac-225. CD33 is expressed in the majority of patients with AML and myelodysplastic syndrome, or MDS, as well as patients with multiple myeloma. The CD33 development program is driven by data from over one hundred treated patients, including a Phase 1/2 trial where Actimab-A produced a remission rate as high as 69% as a single agent. This clinical data is shaping a two-pronged approach for the CD33 program, where at low doses the Company is exploring its use for therapeutic purposes in combination with other modalities and at high doses for use for targeted conditioning prior to bone marrow transplant. Actinium currently has multiple clinical trials ongoing including the Phase 1 Actimab-A CLAG-M and Phase 1/2 Actimab-A venetoclax combination trials and is exploring additional CD33 ARC combinations with other therapeutic modalities such as chemotherapy, targeted agents or immunotherapy.

On December 8, 2020 Imaging Endpoints reported that the U.S. Patent and Trademark Office has issued Patent No. 10,854,338 – "PREDICTING BREAST CANCER RESPONSIVENESS TO HORMONE TREATMENT USING QUANTITATIVE TEXTURAL ANALYSIS" to Imaging Endpoints’ and its inventor, Chief Medical Officer, Ron Korn, M.D., PhD (Press release, Imaging Endpoints, DEC 8, 2020, View Source [SID1234572465]).

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This breakthrough radiomic evaluation tool provides a biomarker for predicting tumor aggressiveness in breast cancer patients, and thus the ability to determine whether less invasive treatment (e.g., hormone therapy) or more invasive treatment (e.g., chemotherapy) is warranted.

Breakthrough radiomic evaluation tool provides biomarker signature for predicting breast cancer tumor aggressiveness.

The technology enables a real-time evaluation that is otherwise available only through an invasive biopsy and avoids the time involved in obtaining and processing the biopsied tissue. Imaging Endpoints is excited to share with the market this new technology that may provide patients and physicians the advantage of faster, less invasive information that is critical to treatment decisions and patient outcomes.

"A reliable imaging signature for guiding treatment decisions based on Luminal vs Basilar type cancer has remained elusive until now," said Ronald Korn, MD, PhD. "The Imaging Endpoints’ invention provides a biomarker for evaluating the treatment options that are most likely to be effective. The signature is derived from aggregate breast tumor imaging data in conjunction with quantitative textural analysis. Imaging Endpoints believes that its technology offers a real-time advantage with rapid results over tests such as Oncotype DX, however additional studies are needed to further validate the correlation of the signature with pathologic variables."

Imaging Endpoints is a pioneer and global leader in analyzing diagnostic images to identify imaging patterns linked to tumor biology. The Company currently offers its advanced imaging technologies through its imaging CRO services for clinical trials, and is actively seeking partners to help commercialize its technologies for routine patient care.

On December 8, 2020 Roche (SIX: RO, ROG; OTCQX: RHHBY) reported that new data on its investigational T-cell engaging bispecific antibodies, mosunetuzumab, glofitamab and cevostamab, were presented at the all-virtual 62nd American Society of Hematology (ASH) (Free ASH Whitepaper) Annual Meeting and Exposition, from 5-8 December 2020, showing encouraging activity across multiple types of blood cancer (Press release, Hoffmann-La Roche, DEC 8, 2020, View Source [SID1234572399]). These antibodies work by binding to two different targets, on two different cells, simultaneously: one on the surface of cancer cells and one on the surface of immune cells called T-cells. This dual targeting approach activates a patient’s existing T-cells to engage and eliminate target cancer cells, offering an innovative approach for the treatment of blood cancers including non-Hodgkin lymphoma (NHL) and multiple myeloma (MM); diseases where treatment options are currently limited, and resistance to, or relapse following, treatment is common. These bispecifics are just one of the novel ‘off-the-shelf’ technologies Roche is exploring, in its quest to improve patient outcomes.

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"The data suggest that our novel bispecific antibodies have potential across multiple types of blood cancers, and supports broad exploration of these new immunotherapy approaches across different patient populations and treatment lines," said Levi Garraway, M.D., Ph.D., Roche’s Chief Medical Officer and Head of Global Product Development. "Lymphoma and multiple myeloma are challenging cancers to treat, especially when patients present with aggressive subtypes or experience multiple relapses, but ‘off-the-shelf’ therapies like these could provide new options that may potentially enable patients to be treated quickly."

Promising responses with mosunetuzumab and glofitamab in non-Hodgkin lymphoma
To date in clinical trials, Roche’s two CD20xCD3 T-cell engaging bispecific antibodies, mosunetuzumab and glofitamab, have shown promising responses across multiple types of NHL, including relapsed or refractory (R/R) follicular lymphoma (FL) and diffuse large B-cell lymphoma (DLBCL). This is reinforced by the latest results from the phase I/Ib GO29781 study in R/R FL, which show that 51.6% of patients (n=32/62) achieved a complete response (CR) when treated with mosunetuzumab.1 High response rates also continue to be seen with glofitamab. For example, new data from the phase I/Ib NP30179 study in R/R NHL show a CR rate of 53.6% in aggressive NHL (n=15/28).2 Additionally, both bispecific antibodies have proven to have manageable safety profiles. One of the most common adverse events (AEs) observed with bispecific antibodies is cytokine release syndrome (CRS), which involves the over activation of immune cells, and is a known risk associated with immunotherapies that activate the body’s own immune system.3 Based on studies so far, CRS events with mosunetuzumab and glofitamab are largely low-grade (mainly Grade 1-2), occur in early treatment cycles, and are mostly reversible.1,2

Beyond the R/R setting, mosunetuzumab and glofitamab are also being investigated in earlier treatment lines, including first-line DLBCL. Initial data with single-agent mosunetuzumab in the phase I/II GO40554 study, show a CR rate of 45.5% (n=10/22) in elderly or unfit patients who are unable to tolerate full-dose immunochemotherapy. Additionally, when mosunetuzumab was combined with chemotherapy in the phase Ib/II GO40515 study, the CR rate was 79.4% (n=27/34). These are the first bispecific antibody studies in 1L DLBCL to report data, and while early, these results support the potential for mosunetuzumab to provide a new, much-needed treatment option for these patients.4,5

Robust development programmes are ongoing for mosunetuzumab and glofitamab, investigating the treatments as monotherapies and in combination with other molecules, as well as more convenient forms of administration such as subcutaneous administration, with several phase III trials planned in the near future.

Encouraging activity with cevostamab in heavily pre-treated patients with multiple myeloma
The third of Roche’s bispecific antibodies in malignant haematology, and latest addition to its pipeline, is cevostamab, a first-of-its kind FcRH5xCD3 bispecific antibody targeting FcRH5 on myeloma cells and CD3 on T-cells. FcRH5 is a unique and differentiated target and is expressed on nearly 100% of myeloma cells. Cevostamab is currently being investigated in the ongoing phase I GO39775 dose-escalation and expansion study in heavily pre-treated patients with MM (with a median of six prior lines of therapy); a population for whom new treatment options are urgently needed.

First clinical safety and efficacy data presented at ASH (Free ASH Whitepaper), showed an encouraging overall response rate of 53% (n=18/34) at active doses. Notably, responses were seen in high-risk patients, including those refractory to five different classes of drug (penta-drug refractory) and those with prior exposure to anti-BCMA therapy. Safety of cevostamab was manageable with the most common treatment-related AE being CRS (76%). The majority of CRS events were Grade 1–2 (Grade 1; 34% and Grade 2; 40%) and occurred in cycle 1. One patient experienced Grade 3 CRS (2%) and no Grade 4 or 5 CRS events were observed.6 Additional biomarker analyses presented at the congress are also helping to further understand the potential of cevostamab in MM and inform its future development, including strategies to mitigate the risk of CRS.7

Roche is excited about the ongoing development of its three bispecific antibodies in malignant haematology and eager to understand their full potential in patients with blood cancers.

About Roche’s CD20xCD3 bispecific antibodies
Roche is currently developing two T-cell engaging bispecific antibodies, mosunetuzumab and glofitamab, designed to target CD20 on the surface of B-cells and CD3 on the surface of T-cells. This dual targeting activates and re-directs a patient’s existing T-cells to engage and eliminate target B-cells by releasing cytotoxic proteins into the B-cells. Mosunetuzumab and glofitamab differ in their structures, and both are being developed by Roche as part of our ongoing haematology research and development strategy to explore multiple bispecific formats, to identify those that may maximise clinical benefits for patients. Mosunetuzumab has a structure similar to that of a natural human antibody in that it has two ‘Fab’ regions, but is different from naturally-occurring antibodies in that one ‘Fab’ region targets CD20 and the other ‘Fab’ region targets CD3. Glofitamab is based on a novel structural format which we call ‘2:1’, which refers to the structure of the antibody. It is engineered to have two ‘Fab’ regions which bind to CD20, and one ‘Fab’ region which binds to CD3. The clinical development programmes for mosunetuzumab and glofitamab include ongoing investigations of these molecules as monotherapies and in combination with other medicines, for the treatment of people with CD20-positive B-cell non-Hodgkin lymphomas, including diffuse large B-cell lymphoma and follicular lymphoma, and other blood cancers.

About cevostamab (FcRH5xCD3 bispecific antibody)
Cevostamab (BFCR4350A) is an FcRH5xCD3 T-cell engaging bispecific antibody designed to target FcRH5 on myeloma cells and CD3 on T-cells. FcRH5 is a unique and differentiated target, expressed on nearly 100% of myeloma cells.8 Cevostamab has a structure similar to that of a natural human antibody in that it has two ‘Fab’ regions, but is different from naturally-occurring antibodies in that one ‘Fab’ region targets FcRH5 and the other ‘Fab’ region targets CD3. This dual targeting activates and re-directs a patient’s existing T-cells to engage and eliminate target FcRH5-expressing myeloma cells by releasing cytotoxic proteins into the myeloma cells.

About the GO29781 study
The GO29781 study [NCT02500407] is a phase I/Ib, multicentre, open-label, dose-escalation study evaluating the safety and pharmacokinetics of mosunetuzumab in people with relapsed or refractory B-cell non-Hodgkin lymphoma. Outcome measures include best objective response rate by revised International Working Group criteria, maximum tolerated dose and tolerability.

About the GO40554 study
The GO40554 study [NCT03677154] is a phase I/II, multicentre, open-label, randomised study evaluating the safety, pharmacokinetics, and preliminary efficacy of mosunetuzumab following first-line diffuse large B-cell lymphoma (DLBCL) immunochemotherapy, or in participants with previously untreated DLBCL who are unable to tolerate full-dose, first-line immunochemotherapy. Primary objectives include complete response rate at time of primary response assessment, as measured by PET-CT, according to Lugano 2014 Response Criteria, and safety. Secondary objectives include assessment of pharmacokinetics, objective response rate, duration of response and progression-free survival.

About the NP30179 study
The NP30179 study [NCT03075696] is a phase I/Ib, multicentre, open-label, dose-escalation study, evaluating the efficacy, safety, tolerability and pharmacokinetics of glofitamab. In this study, glofitamab is assessed as a single-agent and in combination with Gazyva/Gazyvaro (obinutuzumab), following pre-treatment with a one-time, fixed-dose of Gazyva/Gazyvaro, in people with relapsed or refractory B-cell non-Hodgkin lymphoma. Outcome measures include overall response rate, complete response rate per Lugano 2014 criteria, maximum tolerated dose and tolerability.

About the GO39775 study
The GO39775 study [NCT03275103] is a phase I, multicentre trial evaluating the safety and activity of cevostamab (BFCR4350A) monotherapy in adult patients with relapsed or refractory multiple myeloma for which no established therapies are available, appropriate or tolerable. Prior exposure to CAR T-cells, T-cell engaging bispecific antibodies, bispecific T-cell engagers (BiTEs) and antibody-drug conjugates, including those targeting BCMA, is allowed. Primary objectives are to evaluate safety (including the maximum tolerated dose and dose-limiting toxicities) and to identify a recommended phase II dose. Secondary objectives include assessment of pharmacokinetics, activity, immunogenicity and pharmacodynamic biomarkers.

About Roche in haematology
Roche has been developing medicines for people with malignant and non-malignant blood diseases for over 20 years; our experience and knowledge in this therapeutic area runs deep. Today, we are investing more than ever in our effort to bring innovative treatment options to patients across a wide range of haematologic diseases. Our approved medicines include MabThera/Rituxan (rituximab), Gazyva/Gazyvaro (obinutuzumab), Polivy (polatuzumab vedotin), Venclexta/Venclyxto (venetoclax) in collaboration with AbbVie, and Hemlibra (emicizumab). Our pipeline of investigational haematology medicines includes T-cell engaging bispecific antibodies, glofitamab and mosunetuzumab, targeting both CD20 and CD3, and cevostamab, targeting both FcRH5 and CD3; Tecentriq (atezolizumab), a monoclonal antibody designed to bind with PD-L1; and crovalimab, an anti-C5 antibody engineered to optimise complement inhibition. Our scientific expertise, combined with the breadth of our portfolio and pipeline, also provides a unique opportunity to develop combination regimens that aim to improve the lives of patients even further.
(Press release, Hoffmann-La Roche, DEC 8, 2020, View Source [SID1234572399])

On December 8, 2020 THERADIAG (ISIN: FR0004197747, Ticker: ALTER), a company specializing in in vitro diagnostics and theranostics, reported that it has obtained a €1.9 million state-guaranteed loan (Prêt Garanti par l’État or PGE) from a bank syndicate (Press release, Theradiag, DEC 8, 2020, View Source [SID1234572435]).

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The loan is 90% guaranteed by the French government, with an initial maturity of 12 months plus an extension option enabling Theradiag to defer repayment of the principal over a period of up to five years.

On December 8, 2020 Harpoon Therapeutics, Inc. (NASDAQ: HARP), a clinical-stage immunotherapy company developing a novel class of T cell engagers, reported a pipeline update and reported a confirmed partial response based on RECIST v1.1 criteria for its most advanced program, HPN424 for the treatment of metastatic castration-resistant prostate cancer (mCRPC) (Press release, Harpoon Therapeutics, DEC 8, 2020, View Source [SID1234572451]). As of December 1, 2020, in the 160ng/kg cohort, which is the highest fixed dose tested to date, 7 patients have been enrolled and one patient has achieved a confirmed partial response. In addition, 3 patients enrolled in this cohort had serum PSA reductions, including one with a reduction of 50% (PSA50). Dose escalation continues in this trial, in the Phase 1/2a clinical trials for HPN536 as a treatment for ovarian cancer and other mesothelin-expressing solid tumors and in the HPN217 Phase 1/2 clinical trial for multiple myeloma. Step dosing is being utilized in all programs to accelerate testing of higher doses. Dosing of the first patient in the Phase 1/2 trial for Harpoon’s fourth TriTAC development program, HPN328, in small cell lung cancer and other DLL3-associated tumors is expected to occur by the end of the year.

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"We are pleased to provide a trial update to our shareholders today, as well as outline our expectations for 2021. We have made significant progress in all of our clinical development programs in 2020," stated Gerald McMahon, Ph.D., President and CEO of Harpoon Therapeutics. "We are excited to report our first confirmed partial response in the continuing dose escalation trial for HPN424, especially in a heavily pretreated patient population with advanced metastatic disease. We are also excited by the potential for multiple data releases in 2021 on all four of our programs, which we believe represent meaningful milestones for our company."

"We are pleased to report the activity we are seeing with HPN424 in late-stage prostate cancer patients in our highest fixed dose cohort tested to date," said Natalie Sacks, M.D., Chief Medical Officer of Harpoon. "We are implementing step dosing in all of our programs, which allows rapid escalation to higher doses. We look forward to sharing data from these higher-dose cohorts in 2021."

Clinical Program Updates
(All data as of December 1, 2020)

Dose escalation continues in Phase 1/2a trial for HPN424 in the treatment of mCRPC. As of the December 1, 2020 data cutoff date, 69 patients have been dosed across 14 cohorts at fixed doses of 1.3 to 160ng/kg and in step dosing cohorts up to 300ng/kg administered as a weekly intravenous infusion. Enrolled patients had a median of 6 prior systemic therapies, and 76% of patients had prior chemotherapy in the metastatic castration-resistant setting. Ten of 44 patients (23%) with treatment start dates at least 6 months ago remained on study treatment for more than 24 weeks.

At the highest fixed dose tested to date, 160ng/kg, one patient out of 7 has experienced a confirmed partial response with tumor lesion reduction of 43%, and 3 of 7 patients have had serum PSA declines from baseline, including one patient with a PSA reduction greater than 50%.

HPN424 was generally well tolerated and cytokine-related adverse events have been manageable. Reported Grade 3 or higher adverse events have included cytokine release syndrome (CRS) (10%), ALT increase (11%) and AST increase (11%). CRS events and transaminitis have been transient and have not resulted in treatment discontinuation. Dose-limiting toxicities (DLTs) have been observed and have not limited escalation. A maximum tolerated dose (MTD) has not been identified. Presentation of Phase 1 data and initiation of an expansion cohort is planned for the first half of 2021. Interim data from this expansion cohort is anticipated by the end of 2021.

HPN536 (mesothelin TriTAC) Phase 1/2a clinical trial continues escalation. Dosing has occurred across 9 fixed-dose cohorts of 6 to 280ng/kg and 1 step dose cohort up to 600ng/kg. Tumor types treated include late-stage ovarian and pancreatic cancers and peritoneal mesothelioma. Enrolled patients had a median of four prior systemic therapies, and 66% of patients had progressive disease as best response to their most recent prior therapy. Pharmacokinetic analysis shows median half-life of more than 70 hours. Among the relapsed/refractory ovarian cancer patients with at least one post-baseline scan, 8 of 12 (67%) patients showed stability of target lesions.

HPN536 appears to be well tolerated. One CRS grade 3 occurred in the absence of dexamethasone premedication treatment. The CRS resolved, and the patient continued on study with dexamethasone premedication. As of December 1, 2020, no DLTs have been observed. Initiation of an expansion cohort is anticipated by the second half of 2021, with a presentation of Phase 1 data by year-end 2021.

Dose escalation for HPN217 (BCMA TriTAC) Phase 1/2 clinical trial progressing rapidly. Relapsed/refractory multiple myeloma patients have been treated across 6 single-patient fixed dose cohorts of 5 to 810µg, reflecting a more than 100-fold increase in dose in 8 months. HPN217 has been well-tolerated, and no DLTs have been observed as of the December 1, 2020 cutoff date. A presentation of interim data is anticipated in 2021, with initiation of a dose expansion cohort in the second half of 2021.

First patient dosing anticipated for HPN328 (DLL3 TriTAC) by the end of 2020. The first site is open and recruiting for the dose escalation portion of this Phase 1/2 clinical trial. In the first cohort, the patients will receive a flat dose of 15µg of HPN328 administered once weekly by intravenous infusion. Eligible patients include small cell lung cancer patients who have relapsed after platinum chemotherapy and patients with other tumors associated with DLL3 expression. Presentation of initial data is planned for the second half of 2021.

Webcast and Conference Call

Harpoon’s management will host a webcast and conference call at 8 a.m. ET / 5 a.m. PT on December 8, 2020. The live call may be accessed by dialing (866) 951-6894 for domestic callers and (409) 216-0624 for international callers with conference ID code number 1388395. A webcast of the live call will be available online in the investor relations section of the Harpoon website at www.harpoontx.com. A replay of the webcast will be available shortly after the event and can be accessed at the same weblink.