SON-1210 - a novel bifunctional IL-12 / IL-15 fusion protein that improves cytokine half-life, targets tumors, and enhances therapeutic efficacy

Background

The potential synergy between interleukin-12 (IL-12) and IL-15 holds promise for more effective solid tumor immunotherapy. Nevertheless, previous clinical trials involving therapeutic cytokines have encountered obstacles such as short pharmacokinetics, limited tumor microenvironment (TME) targeting, and substantial systemic toxicity.

Methods

To address these challenges, we fused single-chain human IL-12 and native human IL-15 in cis onto a fully human albumin binding (FHAB) domain single-chain antibody fragment (scFv). This novel fusion protein, IL12-FHAB-IL15 (SON-1210), is anticipated to amplify the therapeutic impact of interleukins and combination immunotherapies in human TME. The molecule was studied in vitro and in animal models to assess its pharmacokinetics, potency, functional characteristics, safety, immune response, and efficacy.

Results

SON-1210 demonstrated robust binding affinity to albumin and exhibited the anticipated in vitro activity and tumor model efficacy that might be expected based on decades of research on native IL-12 and IL-15. Notably, in the B16F10 melanoma model (a non-immunogenic, relatively "cold" tumor), the murine counterpart of the construct, which had mouse (m) and human (h) cytokine sequences for the respective payloads (mIL12-FHAB-hIL15), outperformed equimolar doses of the co-administered native cytokines in a dose-dependent manner. A single dose caused a marked reduction in tumor growth that was concomitant with increased IFNγ levels; increased Th1, CTL, and activated NK cells; a shift in macrophages from the M2 to M1 phenotype; and a reduction in Treg cells. In addition, a repeat-dose non-human primate (NHP) toxicology study displayed excellent tolerability up to 62.5 µg/kg of SON-1210 administered three times, which was accompanied by the anticipated increases in IFNγ levels. Toxicokinetic analyses showed sustained serum levels of SON-1210, using a sandwich ELISA with anti-IL-15 for capture and biotinylated anti-IL-12 for detection, along with sustained IFNγ levels, indicating prolonged kinetics and biological activity.

Conclusion

Collectively, these findings support the suitability of SON-1210 for patient trials in terms of activity, efficacy, and safety, offering a promising opportunity for solid tumor immunotherapy. Linking cytokine payloads to a fully human albumin binding domain provides an indirect opportunity to target the TME using potent cytokines in cis that can redirect the immune response and control tumor growth.

Structure and function of a dual antagonist of the human growth hormone and prolactin receptors with site-specific PEG conjugates

Human growth hormone (hGH) is a pituitary-derived endocrine protein that regulates several critical postnatal physiologic processes including growth, organ development, and metabolism. Following adulthood, GH is also a regulator of multiple pathologies like fibrosis, cancer, and diabetes. Therefore, there is a significant pharmaceutical interest in developing antagonists of hGH action. Currently, there is a single FDA-approved antagonist of the hGH receptor (hGHR) prescribed for treating patients with acromegaly and discovered in our laboratory almost 3 decades ago. Here, we present the first data on the structure and function of a new set of protein antagonists with the full range of hGH actions-dual antagonists of hGH binding to the GHR as well as that of hGH binding to the prolactin receptor. We describe the site-specific PEG conjugation, purification, and subsequent characterization using MALDI-TOF, size-exclusion chromatography, thermostability, and biochemical activity in terms of ELISA-based binding affinities with GHR and prolactin receptor. Moreover, these novel hGHR antagonists display distinct antagonism of GH-induced GHR intracellular signaling in vitro and marked reduction in hepatic insulin-like growth factor 1 output in vivo. Lastly, we observed potent anticancer biological efficacies of these novel hGHR antagonists against human cancer cell lines. In conclusion, we propose that these new GHR antagonists have potential for development towards multiple clinical applications related to GH-associated pathologies.

Abstract P3-05-08: High prevalence of splicing variant AR-V7 in triple negative breast carcinoma

The androgen receptor (AR) and its pathway have been implicated in tumorigenesis and progression of breast cancer. Anti-androgen therapy has shown efficacy in the metastatic breast cancer and numerous clinical trials are underway to study efficacy in various clinical settings. 15 splicing variants of AR (AR-Vs) have been described in prostate cancer. Structurally, AR-Vs have insertions of cryptic exons downstream of the exons that encode the DNA-binding domain or deletions of the exons encoding the ligand-binding domain, resulting in a disrupted AR open reading frame and expression of ligand-binding-domain-truncated AR proteins. In prostate cancer, some of the AR-Vs especially AR-V7 are associated with aggressive disease and resistance to anti-AR therapy. The AR-V prevalence in human breast cancer specimens has hitherto not been studied. We aimed at studying the expression of AR-Vs in breast cancer specimens and present the data on AR-V1, AR-V7, AR8, and ARV567, in AR-positive triple negative (TNBC) and ER+/Her2- breast cancer.

Design: 98 cases of TNBC, 40 cases of ER+/Her2 breast cancer and 17 cases with reduction mammoplasty were abstracted from NYULMC pathology database and screened for AR expression by immunohistochemistry (IHC). IHC for AR was performed using antibody clone N-20 (Santa Cruz) at 1:100 dilution. Normal breast tissue was used as internal control and 10% nuclear staining was used for categorizing a tumor as AR positive. A subset of cases which over-expressed AR were macrodissected from formalin fixed paraffin embedded sections with total RNA extracted by using the PureLink® FFPE RNA Isolation Kit (Invitrogen). Reverse-transcription was performed by using the SuperScript® III Reverse Transcriptase Kit (Invitrogen). AR-V expression was presented as cycle number difference to housekeeping gene (delta CT) for real-time PCR or as absolute copy number for digital PCR.

Results: AR+ TNBC and AR+/ER+ cases ranged from stage 1A to IIIA. IHC for AR showed > 10% staining in 27 of 98 TNBC cases and in 39 of 40 ER+/Her2- cases.

AR Positive Prevalence in TNBC and ER+ Breast Carcinoma AR+AR-TNBC2771ER+/Her2-391

AR-V7 was expressed in 11 of 13 AR+/TNBC cases (p < 0.05); AR-V1 and AR-V4 were expressed in 4; ARV8 and ARv567es were expressed in 3 and 2 cases respectively. In 25 AR+/ER+/Her2- cases AR-V7 was expressed in 14; AR-V4 in 9; ARV567 in 5, AR-V1 in 3 cases.

AR Spliced Variant Incidence in TNBC, ER+ and Benign breast tissue Benign (N=17)ER+/AR+ (N=25)TNBC+/AR+(N=13)P ValueAR-V113(12%)4(25%)0.145AR-V419(36%)4(25%)0.35AR-V78(47%)14(56%)11(85%)0.021AR-V801(4%)3(19%)0.474AR-V56715(20%)2(12.5%)0.092

Conclusion: We report expression of various spliced variants in TNBC, ER+/Her2- breast cancer. A statistically significant expression of AR-V7 is seen in TNBC. Since AR-V7 predicts for poor prognosis and lack of response to anti-AR therapy in prostate cancer, AR-V7 expression maybe a useful biomarker to analyze response data in on going breast cancer clinical trials.

Citation Format: Singh B, Deng F-M, Kane Y, Zhan Y, Qi Y, Liu X, Zhang H, Dong Y, Brody R, Wieczorek R, Lee P. High prevalence of splicing variant AR-V7 in triple negative breast carcinoma. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-05-08.

Site specific discrete PEGylation of (124)I-labeled mCC49 Fab' fragments improves tumor MicroPET/CT imaging in mice

The tumor-associated glycoprotein-72 (TAG-72) antigen is highly overexpressed in various human adenocarcinomas and anti-TAG-72 monoclonal antibodies, and fragments are therefore useful as pharmaceutical targeting vectors. In this study, we investigated the effects of site-specific PEGylation with MW 2-4 kDa discrete, branched PEGylation reagents on mCC49 Fab' (MW 50 kDa) via in vitro TAG72 binding, and in vivo blood clearance kinetics, biodistribution, and mouse tumor microPET/CT imaging. mCC49Fab' (Fab'-NEM) was conjugated at a hinge region cysteine with maleimide-dPEG 12-(dPEG24COOH)3 acid (Mal-dPEG-A), maleimide-dPEG12-(dPEG12COOH)3 acid (Mal-dPEG-B), or maleimide-dPEG12-(m-dPEG24)3 (Mal-dPEG-C), and then radiolabeled with iodine-124 ((124)I) in vitro radioligand binding assays and in vivo studies used TAG-72 expressing LS174T human colon carcinoma cells and xenograft mouse tumors. Conjugation of mCC49Fab' with Mal-dPEG-A (Fab'-A) reduced the binding affinity of the non PEGylated Fab' by 30%; however, in vivo, Fab'-A significantly lengthened the blood retention vs Fab'-NEM (47.5 vs 28.1%/ID at 1 h, 25.1 vs 8.4%/ID at 5 h, p < 0.01), showed excellent tumor to background, better microPET/CT images due to higher tumor accumulation, and increased tumor concentration in excised tissues at 72 h by 130% (5.09 ± 0.83 vs 3.83 ± 1.50%ID/g, p < 0.05). Despite the strong similarity of the three PEGylation reagents, PEGylation with Mal-dPEG-B or -C reduced the in vitro binding affinity of Fab'-NEM by 70%, blood retention, microPET/CT imaging tumor signal intensity, and residual 72 h tumor concentration by 49% (3.83 ± 1.50 vs 1.97 ± 0.29%ID/g, p < 0.05) and 63% (3.83 ± 1.50 vs 1.42 ± 0.35%ID/g, p < 0.05), respectively. We conclude that remarkably subtle changes in the structure of the PEGylation reagent can create significantly altered biologic behavior. Further study is warranted of conjugates of the triple branched, negatively charged Mal-dPEG-A.

Factors predicting for postimplantation urinary retention after permanent prostate brachytherapy

PURPOSE

Urinary retention requiring catheterization is a known complication among prostate cancer patients treated with permanent interstitial radioactive seed implantation. However, the factors associated with this complication are not well known. This study was conducted to determine these factors.

METHODS AND MATERIALS

Ninety-one consecutive prostate cancer patients treated with permanent interstitial implantation at our institution from 1996 to 1999 were evaluated. All patients underwent pre-implant ultrasound and postimplant CT volume studies. Isotopes used were (125)I (54 patients) or (103)Pd (37 patients). Twenty-three patients were treated with a combination of 45 Gy of external beam radiation therapy as well as seed implantation, of which only 3 patients were treated with (125)I. Mean pretreatment prostate ultrasound volume was 35.4 cc (range, 10.0-70.2 cc). The mean planning ultrasound target volume (PUTV) was 39.6 cc (range, 16.1-74.5 cc), whereas the mean posttreatment CT target volume was 55.0 cc (range, 20.2-116 cc). Patient records were reviewed to determine which patients required urinary catheterization for relief of urinary obstruction. The following factors were analyzed as predictors for urinary retention: clinical stage; Gleason score; prostate-specific antigen; external beam radiation therapy; hormone therapy; pre-implant urinary symptoms (asymptomatic/nocturia x 1 vs. more significant urinary symptoms); pretreatment ultrasound prostate volume; PUTV; PUTV within the 125%, 150%, 200%, 250%, 300% isodose lines; postimplant CT volume within the 125%, 150%, 200%, 250%, 300% isodose lines; D90; D80; D50; ratio of post-CT volume to the PUTV; the absolute change in volume between the CT volume and PUTV; number of needles used; activity per seed; and the total activity of the implant. Statistical analyses using logistic regression and chi2 were performed.

RESULTS

Eleven of 91 (12%) became obstructed. Significant factors predicting for urinary retention were the total number of needles used (p < 0.038); the pretreatment ultrasound prostate volume (p < 0.048); the PUTV (p < 0.02); and the posttreatment CT volume (p < 0.021). Two of 51 patients (3.9%) requiring 33 or fewer needles (median) experienced obstruction vs. 9 of 40 (22.5%) requiring more than 33 (p < 0.007). If the pretreatment ultrasound prostate volume was 35 cc or less (median), 3 of 43 (7%) vs. 8 of 36 (22%) with a volume greater than 35 cc experienced obstruction (p < 0.051).

CONCLUSION

The number of needles required (perhaps related to trauma to the prostate) and the prostate volumes were significant factors predicting for urinary retention after permanent prostate seed implantation.

Parents cannot detect mild hearing loss in children. First place--Resident Clinical Science Award 1998

Otitis media with effusion is among the most common illnesses of childhood and is often associated with chronic or persistent middle ear effusion (MEE). Our goal was to develop and validate a self-administered parent survey that would identify children at high risk for mild hearing loss caused by MEE. We evaluated 115 children. Parents rated their child's hearing using the HL-7, a 7-item self-administered survey, and a global visual-analog scale. Static admittance and gradient were recorded. Test-retest reliability, internal consistency, and validity of the HL-7 were compared with the 4-frequency pure-tone average (PTA) hearing level (HL) for the better hearing ear. The HL-7 had good test-retest reliability and internal consistency. Survey scores correlated well with the global hearing rating (R = 0.67, P < 0.001) but did not correlate with PTA (R = 0.10, P = 0.29). Tympanometric gradient was unrelated to ear-specific PTA, but not abnormal static admittance (<0.2 cc), which produced a mean 7-dB HL decrease in hearing (ANOVA, P = 0.02). The HL-7 is a reliable and internally consistent measure of parent perception of child hearing, but unfortunately these perceptions are inaccurate for mild hearing loss. Abnormal static admittance is a risk factor for hearing loss.

Exploring teenagers' accounts of bad communication: a new basis for intervention

Interventions to enhance young people's communication are rarely based on research into adolescent communication, but take a more general, analytic, skills-based approach. This paper argues that evidence of young people's communication experiences is an important resource to inform the targeting and content of interventions, which has hitherto been overlooked. An exploratory, hypothesis-generating study of teenagers' accounts of their communication experiences was carried out. Four thousand and forty-eight adolescents aged 13-19 described a recent communication experience with (i) a family member, (ii) a friend or (iii) a non-family adult (professional or official). Self-reported bad communication experiences outweighted good ones only in adolescents' communications with adults outside the family, and there were significant variations across contexts in terms of the purposes, explanations and attributions for perceived bad communication. Implications of the research for future interventions are discussed.

Frontal sinus outflow anatomy

Most of the studies of frontal sinus anatomy were completed 50 to 70 years ago. The information they provide is not necessarily relevant or helpful to the modern rhinologic surgeon who approaches the frontal sinus transnasally and endoscopically. We performed anatomical dissections of the outflow tract of 82 frontal sinuses in 41 cadaver heads to illustrate the various drainage patterns from the frontal sinus to the nose and to correlate these drainage sites with the distance and angle from the pyriform aperture. We found that the frontal sinus drained anterior to the uncinate process in 24 specimens (29.3%) with an average distance of 3.65 cm from the pyriform aperture and 58 degrees from the nasal floor. The frontal sinus drained posterior to the uncinate process in 56 specimens (68.3%) with an average distance of 4.10 cm and 65 degrees from the nasal floor. In this latter group, most of the sinuses (51 specimens) drained into the ethmoid infundibulum. Two of the specimens had a hypoplastic frontal sinus with no outflow tract at all. These findings are different from those described in the early 20th century.

Physician-hastened death. Advisory guidelines for the San Francisco Bay area from the Bay Area Network of Ethics Committees

Recent high court opinions and pending Supreme Court rulings on the legality of physician-hastened death necessitate a pragmatic response from the medical profession. Adopting a "harm reduction" perspective on this contentious topic, the Bay Area Network of Ethics Committees developed practice guidelines for responding to a patient request for hastened death. The guidelines will be offered to the local medical community for use by individuals and health care institutions if the practice of physician-hastened death becomes legal. A multidisciplinary consensus process was used in developing the guidelines, which address clinical, ethical, and procedural concerns.

Assessment of patient satisfaction utilizing the American Pain Society's Quality Assurance Standards on acute and cancer-related pain

An evaluation of patient satisfaction with pain management is one component of a total quality assurance program on pain management recommended by the American Pain Society. This study utilized the patient satisfaction survey recommended by the Quality Assurance Committee of the American Pain Society and was conducted in an acute care, municipal hospital. Seventy-two medical-surgical patients were interviewed about their pain management. Data from the survey suggest that while patients experienced moderate-to-severe pain and had to wait relatively long periods of time for pain medications, in most cases they were satisfied with their overall pain management. Recommendations for conducting patient satisfaction surveys of pain management in acute care settings are reviewed, and methods for interpreting data from these types of surveys are discussed.

A comparative assessment of home versus hospital comprehensive treatment for advanced cancer patients

A prospective comparative analysis of home and hospital comprehensive treatment for advanced non-ambulatory cancer patients was conducted. Patients were assigned to hospital (group A) and home (group B) treatment groups based on geographic location. Home treatment was provided by the Don Monti Home Oncology Medical Extension (HOME) program. A multidisciplinary health team, including an oncologist, oncology nurse, social worker, dietitian, and medical technologist, was transported to the home in a medically equipped van. Services included physical examinations, pain control, psychosocial interventions, chemotherapy and blood transfusions, nutrition consultation, and bereavement counseling. One hundred seventy-four patients were treated at home and 44 in the hospital. Pretreatment characteristics were similar for both groups, with the exception that age under 50 years was more frequent in the hospital group, and home patients were more likely to have gastrointestinal (GI) cancer. Medical benefits for home treatment included decreased narcotic analgesic requirements, decreased hospitalization and length of stay, and improved measurements of fat stores for female patients. Improved survival for home patients was related to Karnofsky performance status, since there was no difference in survival for sicker patients with lower performance status whether they received home or hospital treatment. Patient and family acceptance of home treatment was excellent. Comprehensive home treatment provided by a multispecialty oncology team is an effective alternative to hospitalization for terminal cancer patients.

Rehabilitation in lithium toxicity: case report

Lithium toxicity can produce persistent and possibly permanent neurologic damage involving multiple areas of the nervous system, often including the cerebellum. Such cases, though rare, may continue to occur since lithium salts are widely used. In this report we describe the neurologic presentation, rehabilitation management, and outcome of treatment in such a patient. Her persistent neurologic syndrome was dominated by features of cerebellar dysfunction. Deficits in speech, swallowing, activities of daily living, transfers, and ambulation were identified and a rehabilitation program was implemented. Therapeutic rehabilitative techniques focused on compensatory mechanisms for ataxia and incoordination. Though her basic neurologic status did not change substantially, she did respond well to rehabilitative measures with significant functional gains and the patient was returned to her prior living arrangement.

Are adolescents able and willing to pay the fee for confidential health care?

We studied the ability and willingness of adolescents attending a suburban-based Adolescent Health Service to pay a fee for health care. Self-administered, anonymous questionnaires were distributed to 180 predominantly middle-class adolescent patients prior to the establishment of a fee-for-service payment plan. One hundred sixty-five respondents planned to continue as patients of the Adolescent Health Service; of these, 155 (94%) indicated that they would be able and willing to pay a fee. All of the 155 respondents indicated they could pay $5 per visit, two thirds could pay as much as $10, half could pay $15, and one fifth could pay $20 or more. Sources of fee money would be job earnings, a friend, allowance, and savings; 75% of respondents planned to pay without any help from parents. Analysis revealed few significant correlates of ability and willingness to pay with demographic, socioeconomic, and attitudinal factors. These data demonstrate that, although few of these middle-class adolescent patients indicated that they were able and willing to pay a full fee of $20 or more, most were able and willing to pay more than a token amount for health care.

Assessment of health needs and willingness to utilize health care resources of adolescents in a suburban population

We investigated whether adolescents living in a middle-class suburb believed that their health needs were being met, and the extent to which they were willing to utilize local health care resources for a range of problems. Self-administered, anonymous questionnaires were completed by 649 students in grades 9 through 12. The mean age of respondents was 15.4 years; 52% were female, and 95% white. They had ready access to medical care: 90% used a specific private physician. From a list of 15 health problems, 60% indicated that they had seen a health provider for at least one of them, most often for stomach pains (22%), headaches (18%), and coughing (16%). From an identical list, 48% indicated that there was at least one problem for which they had never seen a health provider but would like to, most often for a weight problem (14%), birth control (10%), and emotional upset (9%). Although 20% regularly used illegal drugs, 24% were sexually active, and 38% thought they had a weight problem, only 1%, 4%, and 10%, respectively, had sought care for these matters. A majority of students would not choose to go to a private physician for care related to sexuality, substance abuse, or emotional upset, and would not be willing to seek care for these problems with their parents' knowledge. Ready access to private primary care did not assure attention to important health needs among these suburban adolescents.

Actinic reticuloid

Actinic reticuloid is a polymorphous dermatosis resulting from a photosensitivity to long wavelength ultraviolet light and occasionally also to visible light, often with clinical and histological resemblance to lymphoma. We describe a patient who is the second American case to be reported with this disease and review the literature. Actinic reticuloid must be distinguished from mycosis fungoides, polymorphous light eruption, persistent light reaction, and contact dermatitis.

An approach to reviewing the effectiveness of programs

Voluntary funding organizations face increasing public demands for accountability in the use of funds. This article presents a model for evaluating the effectiveness of agency programs and discusses its applicability to the process of allocating funds.