Assessment of Combined Nivolumab and Bevacizumab in Relapsed Ovarian Cancer: A Phase 2 Clinical Trial

Importance

To date, single-agent programmed cell death 1 protein 1 (PD-1)/programmed death ligand 1 (PD-L1) immune checkpoint blockade has shown limited activity in recurrent epithelial ovarian cancer. Combination strategies of PD-1/PD-L1 inhibition with antiangiogenic therapy have the potential for synergistic activity through modulation of the microenvironment and represent a potential therapeutic opportunity in this disease.

Objective

To evaluate the activity of combined nivolumab and bevacizumab in women with relapsed ovarian cancer.

Design, Setting, and Participants

A single-arm, phase 2 study enrolled patients between February 8, 2017, and December 29, 2017, at 2 sites in the United States; the primary data analysis was completed July 27, 2018. Thirty-eight women with relapsed epithelial ovarian cancer were enrolled in this study. Participants had disease recurrence within 12 months of their last platinum-based therapy and had received between 1 and 3 lines of prior therapy.

Interventions

Participants received intravenous nivolumab and intravenous bevacizumab once every 2 weeks.

Main Outcome and Measures

The primary end point was objective response rate (ORR) as measured by Response Evaluation Criteria in Solid Tumors 1.1. Secondary end points included evaluation of the ORR by platinum sensitivity, assessment of progression-free survival, assessment of safety data, and investigation of the association of tumor PD-L1 with response to therapy.

Results

Of the 38 women enrolled, 18 had platinum-resistant and 20 had platinum-sensitive disease; mean (SD) age was 63.0 (9.1) years. Eleven patients experienced a confirmed response to nivolumab with bevacizumab (ORR, 28.9%; 95% exact binomial CI, 15.4%-45.9%), with 1 additional unconfirmed response. The ORR was 40.0% (19.1%-64.0%) in platinum-sensitive and 16.7% (95% CI 3.6%-41.4%) in platinum-resistant participants. Thirty-four participants (89.5%) experienced at least 1 treatment-related adverse event; 9 participants (23.7%) experienced a grade 3 or higher treatment-related adverse event. Median progression-free survival was 8.1 months (95% CI, 6.3-14.7 months). In 36 histologic samples for which PD-L1 testing could be performed, 22 samples (61.1%) had a PD-L1 tumoral percentage less than 1, and 14 samples (38.9%) had a PD-L1 tumoral percentage of 1 or greater. Ten responses occurred in patients with PD-L1 tumor percentage less than 1, and 2 in patients with PD-L1 tumor percentages of 1 or greater.

Conclusions and Relevance

The nivolumab with bevacizumab combination appeared to show activity in patients with relapsed ovarian cancer, with greater activity in the platinum-sensitive setting. Alternative combinational strategies may be necessary in the platinum-resistant setting.

Rationale for combination PARP inhibitor and antiangiogenic treatment in advanced epithelial ovarian cancer: A review

Inhibitors of poly(ADP-ribose) polymerase (PARP) and angiogenesis have demonstrated single-agent activity in women with advanced ovarian cancer. Recent studies have aimed to establish whether combination therapy can augment the response seen with PARP inhibitors or antiangiogenic agents alone. This review provides an overview of PARP inhibitors and antiangiogenics as monotherapy in women with advanced ovarian cancer, explores potential mechanisms of action of PARP inhibitor and antiangiogenic combination treatments, reviews efficacy and safety data from trials evaluating this combination, and outlines ongoing and future trials evaluating this combination, discussing these in the context of the current and future treatment landscape for women with advanced ovarian cancer. Sentinel studies evaluating PARP inhibitor (n = 8), antiangiogenic (n = 4), and combination (n = 7) therapy were identified in women with newly diagnosed (n = 7) and recurrent (n = 12) ovarian cancer. PARP inhibitors included olaparib (n = 9), niraparib (n = 4), rucaparib (n = 1), and veliparib (n = 1). Antiangiogenic agents included bevacizumab (n = 7) and cediranib (n = 4). PARP inhibitors combined with antiangiogenics demonstrated efficacy based on objective response rates and progression-free survival (PFS) in the relapsed disease setting. Maintenance therapy with the PARP inhibitor, olaparib, plus antiangiogenic therapy offered a significant PFS benefit versus the antiangiogenic alone in women with newly diagnosed advanced ovarian cancer who tested positive for homologous recombination deficiency. Combination therapy was tolerated, with no new safety signals reported compared with monotherapy trials. PARP inhibitors and antiangiogenics have changed the landscape of ovarian cancer treatment. The PARP inhibitor plus antiangiogenic combination is a novel treatment option that appears promising in the first-line advanced and recurrent ovarian cancer settings, although the role of this combination in recurrent disease requires further elucidation. Defining which patients are candidates for monotherapy or combination therapy is critical, taking into consideration safety profiles of therapies alone or in combination, and how these treatments should be sequenced in clinical practice.

ADAGIO: A phase IIb, open-label, single-arm, multicenter study assessing the efficacy and safety of adavosertib (AZD1775) as treatment for recurrent or persistent uterine serous carcinoma

TPS5612

Background: There is a high unmet medical need for therapies treating uterine serous carcinoma (USC), an aggressive type of endometrial carcinoma with an increased likelihood of recurrence and limited therapeutic options. 5-year overall survival (OS) for USC is estimated to be 35–50% for women with stage I–II disease and 0–15% for women with stage III–IV disease (Acharya et al. Lancet Oncol 2005). USC exhibits high rates of mutation in TP53 ( > 90% of cases), as well as mutations or amplifications in other cell-cycle regulators or oncogenes, including CCNE1, FBXW7, MYC, RB1, and KRAS/ NRAS (Zhao et al. PNAS 2013; Levine DA et al. Nature 2013), which may contribute to increased replication stress and susceptibility to inhibition of the tyrosine kinase WEE1. WEE1 inhibition is expected to release a tumor cell from DNA-damage-induced arrest at the G2/M boundary, so that unrepaired DNA damage may be taken into mitosis, leading to cell death. A Phase II study of the WEE1 inhibitor adavosertib in 34 women with recurrent or persistent USC reported an objective response rate (ORR) of 29.4% and a median duration of response (DoR) of 9.0 months; further correlative analysis and a translational biopsy cohort are planned (Liu et al. J Clin Oncol 2020). This Phase IIb study, ADAGIO, a single-arm, multicenter, global study (NCT04590248), aims to expand on these findings and will evaluate the efficacy and safety of adavosertib in women with recurrent or persistent USC who have previously received platinum-based chemotherapy. Methods: Women aged ≥18 years with histologically confirmed recurrent or persistent USC who have previously received at least one platinum-based chemotherapy regimen for the management of USC and have evidence of measurable disease according to RECIST v1.1 are eligible for this study. Participants with carcinosarcomas are not eligible. Prior receipt of immune checkpoint inhibitors, vascular endothelial growth factor inhibitors and human epidermal growth factor receptor 2 targeted therapy is permitted, with no restriction on the number of prior lines of systemic therapy a participant may have previously received. Approximately 120 eligible participants will receive oral adavosertib 300 mg qd on days 1–5 and 8–12 of a 21-day treatment cycle until disease progression, unacceptable toxicity, withdrawal of consent, or another discontinuation criterion is met. The primary outcome measure is ORR, defined as the percentage of patients with measurable disease at baseline who have a confirmed complete or partial response, as determined by blinded independent central review (RECIST v1.1 assessment every 6 weeks for the first 48 weeks, then every 9 weeks). Secondary outcome measures include DoR, depth of response, progression-free survival, OS, disease control rate, biomarkers, safety, tolerability, and pharmacokinetics. Clinical trial information: NCT04590248.

A phase 3, randomized, double-blind, adaptive, placebo/paclitaxel-controlled study of AVB-S6-500 in combination with paclitaxel in patients with platinum-resistant recurrent ovarian cancer (GOG-3059/ENGOT OV-66/AVB500-OC-004)

TPS5605

Background: The AXL receptor and its activating ligand, GAS6, are important drivers of metastasis and therapeutic resistance in human cancers. This signaling axis represents an attractive target for therapeutic intervention, but the strong picomolar binding affinity between endogenous GAS6 and AXL and the promiscuity of small molecule AXL inhibitors have presented a barrier to specific and potent inhibition of AXL. AVB-S6-500 is a highly sensitive and specific inhibitor of AXL, with ̃200-fold higher affinity than wild-type (WT) AXL. AVB-S6-500 binds GAS6, the sole ligand of AXL, inhibiting its interaction with AXL thereby dramatically reducing AXL signaled invasion and migration of highly metastatic cells in vitro and inhibiting metastatic disease in nonclinical models of aggressive human cancers. A Phase 1b study in platinum resistant ovarian cancer showed no dose limiting toxicities and established a recommended Phase 2 dose of 15mg/kg administered every 2 weeks. Longer progression free survival (PFS) and overall survival (OS) times were observed in patients who had not been previously treated with bevacizumab. Furthermore, retrospective analyses demonstrated that serum soluble AXL to GAS6 ratio may identify patients more likely to respond to this therapy. Methods: Patients with high grade serous, platinum resistant ovarian cancer, who have received no more than 4 prior therapy regimens will be randomized 1:1 to AVB-500 + PAC or PAC + placebo. Patients will be stratified by recurrence after last platinum regimen (<3, 3-6 months), prior lines (1-2, 3-4), and prior bevacizumab (yes, no). The primary endpoint is PFS by RECIST v 1.1 as assessed by the investigator, with OS a key secondary endpoint. The study design is adaptive; with two interim analyses addressing conditional power in the bevacizumab treated subset, and in a serum soluble AXL, GAS6 biomarker subset, respectively, with interim results used to define the final target population. Simulations confirm a nominal one-sided type 1 error below 0.025, and show >90% statistical power for PFS under the following assumptions of PFS medians. Study recruitment began in Q1. Clinical trial information: NCT04729608.

A phase 2, two-stage study of avelumab and axitinib in patients with mismatch repair proficient (MMR-P) recurrent or persistent endometrial cancer (EC)

TPS5609

Background: Despite significant strides in understanding the molecular pathogenesis of EC, there remain few effective therapies for recurrent disease. Deeper insight into the roles of disordered tumor vasculature and HIF1α- and VEGF-mediated immunosuppressive effects on myeloid-derived suppressor cells, T-cells, and PD-L1 expression contributed to the development of new targeted regimens. Activity of pembrolizumab and lenvatinib was demonstrated in a phase 2 trial in MMR-P EC (NCT02501096). By inhibiting VEGF receptor (VEGFR) and PD-L1 signaling, immunologically “cold” tumors may become inflamed. However, there are concerns regarding the toxicity of pembrolizumab/lenvatinib and alternatives are sought. The combination of the anti-PD-L1 antibody avelumab with axitinib, an inhibitor of VEGFR 1-3 and PDGFR with more potent IC50 inhibitory activity than lenvatinib, has also shown synergistic activity and is FDA approved as first line treatment for patients with renal cell cancer. We therefore hypothesized that this combination would be well tolerated and efficacious in recurrent MMR-P EC. Methods: This is an investigator-initiated, phase 2, two-stage single cohort trial evaluating avelumab with axitinib in recurrent or persistent EC. Participants must have MMR-P EC of any histology and have received at least one chemotherapeutic regimen, with no upper limit on the number of prior lines received. Prior use of immune checkpoint (IC) inhibitors is excluded. Treatment consists of avelumab 800mg IV every 2 weeks and axitinib 5mg orally twice daily. Co-primary endpoints are progression-free survival at 6 months (PFS6) and objective response rate by RECIST 1.1. Translational objectives include characterization of tumor-infiltrating lymphocytes, infiltrating myeloid cells, expression of IC markers, and whole exome sequencing to evaluate mutations in genes related to DNA repair and immunologic response. This is a two-stage design in the method of Sill et al, with 16 participants anticipated in stage 1 and 19 participants in stage 2, for a total of 35 participants. Accrual is ongoing. Clinical trial information: NCT02912572.

Phase 1b study of GAS6/AXL inhibitor (AVB-500) in recurrent, platinum-resistant ovarian carcinoma

5566

Background: AVB-500 is a first-in-class Fc fusion protein that binds the GAS6 ligand thereby inhibiting AXL signaling. Both GAS6 and AXL are highly expressed in high-grade serous ovarian cancer (HSGOC). This study evaluated safety, tolerability, and preliminary efficacy of AVB-500 in combination with pegylated liposomal doxorubicin (PLD) and paclitaxel (Pac) and determine the recommended Phase 2 dose (RP2D). Methods: Patients were enrolled in escalating dose cohorts of AVB-500 10mg/kg to 20mg/kg q2 weeks in combination with weekly Pac 80mg/m2 D1, 8, 15 q28 days or PLD 40mg/m2 D1 q28 days and assess for safety, pharmacokinetics, pharmacodynamics, and response by investigator, via RECIST v1.1. Results: A total of 53 patients with platinum-resistant HGSOC (PROC) were enrolled. A total of 23 patients received Pac + AVB-500 and 30 patients received PLD + AVB-500. Grade 3 or 4 treatment-related adverse events were observed in 4/23 (17%) and 2/30 (7%) PAC and PLD, respectively. No patients discontinued therapy due to an adverse event. Most events were related to known chemotherapy side effects. RP2D was identified as 15mg/kg. Confirmed overall response rate (ORR) with Pac+AVB-500 was 35% (8/23) including 2 CRs and 11% (3/28) in the PLD+AVB-500 subgroup. ORR was 19% (3/16) in patients with platinum free interval (PFI) of < 3 months versus (vs) 23% (8/35) in patients with PFI of 3-6 months. ORR was 11% (2/18) in patients with 1 prior treatment vs 27% (9/33) in patients with 2-3 prior lines of therapy. ORR in patients without prior bevacizumab was 33% (9/27) vs 8% (2/24) in those with prior bevacizumab. Patients treated with Pac combination and whose AVB-500 trough levels were above the minimal efficacious concentration (MEC) of 13.8mg/L achieved the greatest benefit with ORR, median PFS, and median OS of 43% (6/14), 3.9 months, and 17.8 months vs 22% (2/9), 2.8 months, and 8.7 months observed in those whose trough was below the MEC. Among the Pac treated subgroup, the ORR was 47% (13% CR) vs 0% for those with sAXL/GAS6 ratios > 0.773 compared to ratios <0.773. 67% of patients had baseline sAXL/GAS6 > 0.773. Conclusions: AVB-500 is a novel Fc fusion protein that binds the GAS6 ligand and inhibits AXL signaling. AVB-500 was well-tolerated in combination with Pac or PLD. This Ph1b trial suggested a higher ORR in the Pac treated subgroup, with C1D15 trough levels > 13.8mg/L (most consistently achieved at the 15mg/kg dose level). Exploratory analyses suggested that improved ORR may be observed in patients who have not been exposed to bevacizumab. The serum sAXL/GAS6 ratio may be a potential biomarker of pathway activation and identify patients who most benefit from Pac+AVB-500. The ORR in patients with PFI < 3 months or who had > 1 line of prior therapy were similar to those with 3-6 months PFI or ≤1 lines of therapy. Further development of AVB-500 15 mg/kg q2 weeks in combination with Pac is warranted in PROC. Clinical trial information: NCT03639246.

A phase I/II, multicenter, open-label study of REGN5668 (mucin [MUC]16 x CD28 bispecific antibody [bsAb]) with cemiplimab (programmed death [PD]-1 Ab) or REGN4018 (MUC16 x CD3 bsAb) in recurrent ovarian cancer (rOVCA)

TPS5602

Background: There is a high unmet need in rOVCA treatment, with 14,000 deaths/year in the US and a 30%‒40% 5-year overall survival rate in patients (pts) with advanced disease. REGN5668 and REGN4018 are human IgG4-based bsAbs that bridge ovarian MUC16+ tumor cells to CD28 and CD3, respectively, on T-cells to stimulate cytotoxicity. Cemiplimab is a human monoclonal Ab that blocks PD-1 binding to PD-ligand(L)1 and PD-L2. REGN5668 demonstrated increased preclinical anti-tumor activity with PD-1 inhibition or REGN4018 relative to each monotherapy. A Phase I/II study of REGN4018 alone or with cemiplimab is ongoing. Methods: This first-in-human study (NCT04590326) will assess safety, tolerability, pharmacokinetics, and preliminary anti-tumor activity of REGN5668 with cemiplimab (Module 1) or REGN4018 (Module 2) in pts with rOVCA. Key inclusion criteria include histologically confirmed diagnosis of advanced epithelial ovarian (except carcinosarcoma), fallopian tube, or primary peritoneal cancer; serum CA-125 level ≥2x upper normal limit; ≥1 prior-line of platinum-based therapy; prior treatment with or intolerance to available standard-of-care therapy. Exclusion criteria include recent biologic therapy ( < 5 half-lives or 28 days, whichever is longer, except < 3 half-lives for bevacizumab or other nonimmunomodulatory Abs with half-lives > 7 days); approved conventional therapy (except biologics or immunotherapy) < 3 weeks (wks) or investigational agents < 4 wks prior to first study dose; and anti–PD-L1 therapy < 5 half-lives prior to first study dose. This two-phase study includes dose escalation (a 4+3 design modified from 3+3) and expansion phases. In Module 1, ≤84 pts will receive 3–4 wks of REGN5668 monotherapy lead-in at assigned intravenous (IV) weekly (QW) dose levels, followed by REGN5668 QW combined with cemiplimab IV every 3 wks. In Module 2, ≤106 pts will receive 4–5 wks of REGN4018 QW IV lead-in, followed by REGN4018 full QW dose combined with REGN5668 at initial and full assigned QW doses. In expansion, REGN5668+cemiplimab and REGN5668+REGN4018 combination regimens will each recruit 20 pts in stage 1 and 30 pts in stage 2 using a Simon two-stage design. In escalation, primary endpoints are dose-limiting toxicities, serious and treatment-emergent adverse events (TEAEs), deaths, laboratory abnormalities (Grade ≥3), concentrations of REGN5668 in serum alone and in each combination regimen; key secondary endpoint is objective response rate (ORR) per Response Evaluation Criteria in Solid Tumors (RECIST) 1.1. In expansion, primary endpoint is ORR by RECIST 1.1 for each combination; key secondary endpoints are TEAEs, serious AEs, deaths. Key exploratory endpoints are correlation between clinical efficacy endpoints and baseline protein expression levels of MUC16 and PD-L1. Clinical trial information: NCT04590326.

EFFORT: EFFicacy Of adavosertib in parp ResisTance: A randomized two-arm non-comparative phase II study of adavosertib with or without olaparib in women with PARP-resistant ovarian cancer

5505

Background: Wee1 phosphorylates and inhibits cyclin-dependent kinases 1 and 2 and is involved in regulation of the intra-S and G2/M cell cycle checkpoint arrest for premitotic DNA repair. The Wee1 inhibitor, adavosertib, has demonstrated activity alone and in combination with olaparib in PARP inhibitor (PARPi)-resistant preclinical models. We sought to evaluate efficacy of adavosertib (A) with or without olaparib (O) in a phase II noncomparative study of recurrent PARPi-resistant ovarian cancer. Methods: Women with recurrent ovarian, fallopian tube or primary peritoneal cancer with documented progressive disease on a PARPi were eligible. All patients (pts) had measurable disease and adequate end organ function. On the A arm, pts received A 300mg PO daily on days 1-5 and 8-12 of a 21-day cycle. On the A/O arm, pts received A 150mg PO BID on days 1-3 and 8-10 and O 200mg PO BID on days 1-21 of a 21-day cycle. Primary endpoint was objective response per RECIST 1.1 and was assessed every 2 cycles. Clinical benefit rate (CBR) was defined as proportion of pts with objective response or stable disease > 16 weeks. Progression free survival (PFS) was assessed using the Kaplan Meier method and calculated from date of treatment initiation to earliest date of progression, death, or last visit. Results: 116 pts were screened with 80 pts enrolled and randomized (A: n=39, A/O: n=41). Median age was 60 years (range 36-76) and the majority of pts had platinum resistant disease (64%) and high grade serous histology (98%). Pts received a median of 4 prior therapies (range 1-11) and 48% had germline or somatic BRCA mutations. There were 35 pts evaluable for response in each arm. Table demonstrates efficacy data. On the A arm, Grade 3/4 toxicities occurred in 51% of pts, most commonly neutropenia (13%), thrombocytopenia (10%), and diarrhea (8%). 28 (72%) pts required at least one dose interruption and 20 (51%) required dose reduction. On the A/O arm, Grade 3/4 toxicities occurred in 76% of pts, most commonly thrombocytopenia (20%), neutropenia (15%), diarrhea (12%), fatigue (12%), and anemia (10%). 36 (88%) of pts required at least one dose interruption, 29 (71%) required dose reduction, and 4 (10%) did not restart due to toxicity. Conclusions: A given alone and in combination with O demonstrated efficacy in pts with PARPi-resistant ovarian cancer. Although grade 3 and 4 toxicities were observed on both arms, these were generally manageable with supportive care, dose interruptions and dose reductions as needed. Additional translational analyses are ongoing to clarify which pts received clinical benefit. Clinical trial information: NCT03579316. [Table: see text]

A phase 2, two-stage study of mirvetuximab soravtansine (IMGN853) in combination with pembrolizumab in patients with microsatellite stable (MSS) endometrial cancer (EC)

TPS5611

Background: Folate receptor-alpha (FRα) is expressed on endometrial cancer (EC) cells and is associated with poor prognosis. Mirvetuximab soravtansine (ImmunoGen), an antibody drug conjugate (ADC) comprising a FRα-binding antibody, cleavable linker, and the tubulin-disrupting maytansinoid DM4, showed tolerability and single agent activity in a Phase 1 study with dose expansion in FRα+ advanced/recurrent EC (NCT01609556) and also when combined with chemotherapy, bevacizumab as well as pembrolizumab (NCT02606305). In addition to having direct target-mediated cytotoxicity, ADCs also stimulate the local tumor immune microenvironment. Mirvetuximab soravtansine has been shown to activate monocytes and promote phagocytosis of mirvetuximab-treated FRα-positive tumor cells through a mechanism of Fc-FcγR interaction. Further, the combination of ADCs with immune checkpoint inhibitors (ICI) can overcome primary resistance to immunotherapy in murine models. Given the low response of MSS endometrial cancers to PD-1 blockade, we hypothesized that addition of mirvetuximab may enhance response of these tumors to immunotherapy. Methods: This is a Phase 2, single cohort study of mirvetuximab soravtansine with pembrolizumab in recurrent or persistent EC. Patients must have advanced or recurrent MSS serous endometrial cancer with at least 1 and up to 3 prior lines of therapy. Confirmation of FRα expression (with PS2+ staining intensity in ≥ 50% of cells, performed centrally at Ventana Medical Systems, Inc) is required. Prior receipt of ICI is excluded. Patients will receive the combination of mirvetuximab soravtansine 6 mg/kg AIBW IV and pembrolizumab 200 mg IV administered every 21 days. The co-primary endpoint is progression-free survival at 6 months (PFS6) and objective response rate (ORR) by RECIST 1.1. Translational objectives include assessment of tumor infiltrating lymphocytes (TILs), expression of immune checkpoint markers, and whole exome sequencing (WES) for DNA repair pathway mutations, neoantigens, and polymorphisms in immunologically relevant genes. Statistical considerations are for a Simon two-stage optimal design with 16 patients in Stage 1 and 19 patients in Stage 2, to a total of 35. Prespecified activity for the first stage of accrual was met, and second stage accrual began November 2020. Clinical trial information: NCT03835819.

A first-in-human study of AO-176, a highly differentiated anti-CD47 antibody, in patients with advanced solid tumors

2516

Background: AO-176 is a humanized IgG2 antibody that specifically targets CD47. Expressed by multiple tumor types, CD47 binds to signal regulatory protein a (SIRPa) on phagocytes, including macrophages and dendritic cells. The CD47-SIRPa complex results in a “don’t eat me” signal that allows the tumor to escape removal by the innate immune system, disabling the generation of an adaptive immune response. The differentiated mechanisms of action of AO-176 include promotion of phagocytosis, direct tumor cell killing through programmed cell death type III and induction of damage associated molecular patterns/immunogenic cell death, preferentially binding to tumor cells vs. normal cells, and enhanced binding at an acidic pH as found in tumor microenvironments. AO-176 has negligible binding to RBCs. Methods: In a phase 1/2 first-in-human study (NCT03834948) of AO-176, pts with advanced solid tumors associated with high CD47 expression and an ECOG PS of 0-1 were enrolled into escalating dose cohorts of AO-176 given IV every 7 days. Objectives included evaluation of safety, dose-limiting toxicity (DLT) and recommended phase 2 dose (RP2D), antitumor activity, pharmacokinetic (PK) parameters and exploratory biomarkers. Results: As of 4 Jan 2021, 27 pts were enrolled (median age 64 years; 67% female; 67% ECOG PS 1; median [range] of 4 [1-7] prior therapies for metastatic disease). Dose levels of 1, 3, 10, 20 and 20 (using step-up dosing) mg/kg were evaluated in >250 infusions. Most common (>10%) treatment-related adverse events (TRAEs) of any grade were thrombocytopenia and infusion-related reaction (IRR) (33% each), anemia (22%) with no evidence of hemolysis, nausea (19%), and fatigue (15%). The only G3+ TRAE occurring in >10% of pts was asymptomatic, brief thrombocytopenia (22%). No platelet transfusions were given. DLTs included IRRs in 2 pts dosed at 20 mg/kg, and asymptomatic thrombocytopenia and a cerebrovascular accident in 1 pt each in the 20 mg/kg step-up cohort. The RP2D was 10 mg/kg. Implementation of additional pre-medication and a 6-hr infusion duration in cycle 1 eliminated subsequent IRRs. Dexamethasone tapering and shortening of the infusion duration to 2 hrs was successful in all pts after cycle 1. Interim PK analysis of AO-176 demonstrated consistent exposure with linear PK. The T1/2 was ̃5 days. One pt with endometrial carcinoma who had not responded to any of 4 prior systemic regimens had a confirmed PR and remains on study for >1 year. 7 pts had SD as a best response, with 2 pts (endometrial carcinoma, gastric cancer) on study for >6 mos. Conclusions: AO-176 is a well-tolerated, differentiated anti-CD47 therapeutic. Durable anti-tumor activity was observed. Evaluations of AO-176 in combination with paclitaxel in pts with select solid tumors (NCT03834948) and as a single-agent in pts with multiple myeloma (NCT04445701) are ongoing. Clinical trial information: NCT03834948.

Phase II Study of the WEE1 Inhibitor Adavosertib in Recurrent Uterine Serous Carcinoma

PURPOSE

Uterine serous carcinoma (USC) is a distinct histologic subtype of endometrial cancer, with molecular characteristics suggesting frequent cell-cycle dysregulation paired with a high level of oncogene-driven replication stress. Adavosertib is a potent and selective oral inhibitor of the WEE1 kinase, a key regulator of the G2/M and S phase cell-cycle checkpoints. Because cells with impaired cell-cycle regulation and high replication stress may be vulnerable to WEE1 inhibition, we conducted this study to assess the activity of adavosertib monotherapy in women with recurrent USC.

PATIENTS AND METHODS

This was a single-arm two-stage phase II study with coprimary end points of objective response rate (ORR) and rate of progression-free survival at 6 months (PFS6). Women with recurrent USC were treated with adavosertib monotherapy at a starting dose of 300 mg orally once daily days 1 through 5 and 8 through 12 of a 21-day cycle until disease progression.

RESULTS

In 34 evaluable patients, 10 total responses (one confirmed complete response, eight confirmed partial responses, and one unconfirmed partial response) were observed with adavosertib monotherapy, for an ORR of 29.4% (95% CI, 15.1 to 47.5). Sixteen patients were progression-free at 6 months, for a PFS6 rate of 47.1% (95% CI, 29.8 to 64.9). Median PFS was 6.1 months, and median duration of response was 9.0 months. Frequent treatment-related adverse events (AEs) included diarrhea (76.5%), fatigue (64.7%), nausea (61.8%), and hematologic AEs. No clear correlation of clinical activity with specific molecular alterations was observed in an exploratory biomarker analysis.

CONCLUSION

Adavosertib monotherapy demonstrated encouraging and durable evidence of activity in women with USC, and further investigation of this agent in this cancer and biomarkers of activity are indicated.

Enhanced Efficacy of Aurora Kinase Inhibitors in G2/M Checkpoint Deficient TP53 Mutant Uterine Carcinomas Is Linked to the Summation of LKB1-AKT-p53 Interactions

Simple Summary

Cancers arising from the lining of the uterus, endometrial cancers, are the most common gynecologic malignancy in the United States. Once endometrial cancer escapes the uterus and grows in distant locations, there are limited therapeutic options. The most aggressive and lethal endometrial cancers carry alterations in the protein p53, which is a critical guardian of many cellular functions. The role of these p53 alterations in endometrial cancer is not well understood. The goal of this work was to use p53 altered models of endometrial cancer to understand which, if any, therapeutically targetable vulnerabilities these p53 alterations may confer in endometrial cancer. Here we show that many of these p53 altered cells have problems with cell division which can be targeted with novel single and combination therapies. These discoveries may lead to relevant new therapies for difficult to treat advanced stage endometrial cancers.

Abstract

Uterine carcinoma (UC) is the most common gynecologic malignancy in the United States. TP53 mutant UCs cause a disproportionate number of deaths due to limited therapies for these tumors and the lack of mechanistic understanding of their fundamental vulnerabilities. Here we sought to understand the functional and therapeutic relevance of TP53 mutations in UC. We functionally profiled targetable TP53 dependent DNA damage repair and cell cycle control pathways in a panel of TP53 mutant UC cell lines and patient-derived organoids. There were no consistent defects in DNA damage repair pathways. Rather, most models demonstrated dependence on defective G2/M cell cycle checkpoints and subsequent upregulation of Aurora kinase-LKB1-p53-AKT signaling in the setting of baseline mitotic defects. This combination makes them sensitive to Aurora kinase inhibition. Resistant lines demonstrated an intact G2/M checkpoint, and combining Aurora kinase and WEE1 inhibitors, which then push these cells through mitosis with Aurora kinase inhibitor-induced spindle defects, led to apoptosis in these cases. Overall, this work presents Aurora kinase inhibitors alone or in combination with WEE1 inhibitors as relevant mechanism driven therapies for TP53 mutant UCs. Context specific functional assessment of the G2/M checkpoint may serve as a biomarker in identifying Aurora kinase inhibitor sensitive tumors.

Timing of continuous renal replacement therapy in severe acute kidney injury patients with fluid overload: A retrospective cohort study

PURPOSE

We aimed to evaluate the association of early versus late initiation of Continuous renal replacement therapy (CRRT) with mortality in patients with fluid overload.

METHODS

This was a retrospective cohort study of patients with fluid overload (FO) treated with CRRT due to severe acute kidney injury (AKI) between January 2015 and December 2017 in a mixed medical intensive care unit of a teaching hospital in Beijing, China. Patients were divided into early (≤15 h) and late (>15 h) groups based on the median time from ICU admission to CRRT initiation. The primary outcome was all-cause mortality at day 60. Multivariable Cox model analysis was used for analysis.

RESULTS

The study patients were male predominant (84/150) with a mean age of 64.8 ± 16.7 years. The median FO value before CRRT initiation was 10.1% [6.2-16.1%]. The 60-day mortality rates in the early vs the late CRRT groups were 53.9% and 73%, respectively. On multivariable Cox modelling, the late initiation of CRRT was independently associated with an increased risk of death at 60 days (HR 1.75, 95% CI 1.11-2.74, p = 0.015).

CONCLUSIONS

Early initiation of CRRT was independently associated with survival benefits in severe AKI patients with fluid overload.

Lived experiences of women reporting fatigue during PARP inhibitor maintenance treatment for advanced ovarian cancer: A qualitative study

OBJECTIVE

Oral PARP inhibitors (PARPi) have dramatically changed the treatment landscape for patients with advanced ovarian cancer. However, a subset of patients discontinue PARPi due to treatment-related fatigue. The current study sought to explore patients' lived experiences with fatigue on PARPi.

METHODS

We conducted individual semi-structured interviews with N = 23 women receiving PARPi for advanced ovarian cancer who reported moderate to severe fatigue. Audiotaped interviews were transcribed and we used thematic analysis to code transcripts for emergent themes.

RESULTS

Four overarching themes emerged. First, participants described their fatigue as milder than what they experienced on intravenous chemotherapy, but noted it consistently limited their daily activities, including work, and interfered with participation in family and social events. Second, fatigue negatively impacted participants' sense of self and identity. Third, most wanted to continue treatment and believed discontinuing PARPi would lead to a cancer recurrence or death. Finally, many participants reported that their support networks were unaware of their ongoing cancer treatment or the resulting fatigue; a situation that may prove isolating and result in reduced social support.

CONCLUSIONS

Our findings underscore patients' persistent experience of fatigue on PARPi, the impact of fatigue on multiple domains of functioning, and a lack of understanding of side effects resulting from oral maintenance treatments among patients' social networks. Our findings highlight the need for interventions to address treatment-related fatigue to limit the negative impacts of fatigue on ovarian cancer patients' well-being.

FAM83H and Autosomal Dominant Hypocalcified Amelogenesis Imperfecta

Autosomal dominant hypocalcified amelogenesis imperfecta (ADHCAI; OMIM #130900) is a genetic disorder exhibiting severe hardness defects and reduced fracture toughness of dental enamel. While the condition is nonsyndromic, it can be associated with other craniofacial anomalies, such as malocclusions and delayed or failed tooth eruption. Truncation mutations in FAM83H (OMIM *611927) are hitherto the sole cause of ADHCAI. With human genetic studies, Fam83h knockout and mutation-knock-in mouse models indicated that FAM83H does not serve a critical physiologic function during enamel formation and suggested a neomorphic mutation mechanism causing ADHCAI. The function of FAM83H remains obscure. FAM83H has been shown to interact with various isoforms of casein kinase 1 (CK1) and keratins and to mediate organization of keratin cytoskeletons and desmosomes. By considering FAM83H a scaffold protein to anchor CK1s, further molecular characterization of the protein could gain insight into its functions. In this study, we characterized 9 kindreds with ADHCAI and identified 3 novel FAM83H truncation mutations: p.His437*, p.Gln459*, and p.Glu610*. Some affected individuals exhibited hypoplastic phenotypes, in addition to the characteristic hypocalcification enamel defects, which have never been well documented. Failed eruption of canines or second molars in affected persons was observed in 4 of the families. The p.Glu610* mutation was located in a gap area (amino acids 470 to 625) within the zone of previously reported pathogenic variants (amino acids 287 to 694). In vitro pull-down studies with overexpressed FAM83H proteins in HEK293 cells demonstrated an interaction between FAM83H and SEC16A, a protein component of the COP II complex at endoplasmic reticulum exit sites. The interaction was mediated by the middle part (amino acids 287 to 657) of mouse FAM83H protein. Results of this study significantly extended the phenotypic and genotypic spectrums of FAM83H-associated ADHCAI and suggested a role for FAM83H in endoplasmic reticulum-to-Golgi vesicle trafficking and protein secretion (dbGaP phs001491.v1.p1).

[Predicting the prognosis for severe brain injury patients: short-latency somatosensory evoked potential combined with electroencephalogram reactivity]

Objective: To explore the the effectiveness of using short-latency somatosensory evoked potential(SLSEP) combined with electroencephalogram(EEG) reactivity to predict the prognosis of severe brain injury(SBI) patients. Methods: Consecutive patients with SBI admitted in neurosurgery intensive care unit(NSICU) at Xiangya Hospital of Central South University from July 2018 to January 2019 were prospectively collected. SLSEP and EEG were recorded in these patients in NSICU within two weeks after injury onset. EEG reactivity(EEG-R) was tested during EEG signal stabilization. In addition, the concentrations of serum neuron-specific enolase (NSE) and S100 protein were also detected. All patients were evaluated with Glasgow Outcome Scale(GOS) during 12 months' follow-up. GOS grade 3 to 5 was defined as favorable group, and GOS grade 1 to 2 was defined as unfavorable group. The association of relevant predictors with patient's prognosis was assessed. The area under the receiver operating characteristic (ROC) curve (AUC) was used to evaluate each potential predictor. Results: Forty-three patients were included in the study, with 26 patients of favorable outcomes and 17 patients with unfavorable prognosis. Univariate analysis revealed that the Glasgow Coma Scale (GCS) score, the concentration of serum NSE, EEG-R, the amplitude of SLSEP were all associated with the prognosis after 12 months' follow-up. Moreover, the AUC for prediction of favorable prognosis by GCS, NSE, EEG-R, SLSEP was 0.661(95%CI: 0.493-0.829), 0.697(95%CI: 0.531-0.862), 0.718(95%CI: 0.557-0.879) and 0.758(95%CI: 0.609-0.907) respectively. However, there was no significant difference of age, gender, pupillary light reflex and S100 protein between the two groups. Furthermore, multiple logistic regression analysis showed that only SLSEP amplitude (OR=2.058, 95%CI: 0.867-4.888) and EEG-R(OR=3.748, 95%CI: 0.857-16.394) were independent predictors of favorable prognosis, and the prognostic model containing these two variables yielded an predictive performance with an AUC of 0.798. Conclusion: The higher amplitude of SLSEP and the existence of EEG-R are predictors of good prognosis in SBI patients, and the combined use of SLSEP and EEG-R in predicting the prognosis of SBI patients is more reliable.

Clinical assays for assessment of homologous recombination DNA repair deficiency

Homologous recombination DNA repair deficiency (HRD) is a functional defect in homologous recombination DNA repair, arising from germline or somatic mutations in BRCA1/2 or other mechanisms. Cells with HRD are more sensitive to platinum and poly(ADP-ribose) polymerase inhibitors (PARPi). HRD generates permanent changes in the genome with specific, quantifiable patterns ("genomic scars"). Clinical tests for HRD, such as the Myriad genomic instability score and Foundation Medicine loss of heterozygosity test, aim to predict the presence of HRD based on genomic features. Clinical trials of PARPi in ovarian cancer have evaluated genetic mutations and HRD genomic assays as potential biomarkers of response. Patients with HRD due to BRCA1/2 mutations are more likely to respond to PARPi than those with wild-type (WT) BRCA1/2. In some clinical trials, patients with WT BRCA1/2 who were predicted to be HRD by a genomic test exhibited greater clinical benefit from PARPi than patients with WT BRCA1/2 and no evidence of HRD. HRD tests therefore hold promise as predictive biomarkers for PARPi and other DNA-damaging agents. However, HRD tests vary in terms of the specific genomic features they measure, and the methods used to determine thresholds defining patients with HRD. Also, HRD test results and PARPi responses can be discordant: for instance, tumors with reversion mutations that restore HR function still exhibit a "genomic scar" of HRD, and PARPi resistance mechanisms independent of HR can result in lack of PARPi response despite HRD. Emerging methods to predict HRD, including genomic and functional assays, may overcome some of these challenges. Evaluation of HRD in the clinical setting is an important tool that has potential to aid patient selection for PARPi and other DNA-damaging agents in ovarian cancer, but understanding the details of these tests and their limitations is critical to ensure their optimal clinical application.

[Establishment of a recombinase-aided isothermal amplification assay for nucleic acid detection of Angiostrongylus cantonensis]

OBJECTIVE

To establish a recombinase-aided isothermal amplification (RAA) assay for the nucleic acid detection of Angiostrongylus cantonensis.

METHODS

The internal transcribed spacer-1 (ITS1) gene sequence of A. cantonensis was used as the detection target sequence, and the specific primers and probes were designed and synthesized, followed by screening of the primers and probes with the highest specificity, to establish the basic and fluorescent RAA assay for nucleic acid detection of A. cantonensis. The sensitivity of the fluorescent RAA assay was evaluated by using the target gene fragment sequence-contained recombinant plasmids at various copy numbers and the genomic DNA from A. cantonensis as the template DNA samples, and the specificity of the fluorescent RAA assay was evaluated by using the genomic DNA from A. cantonensis, Schistosoma mansoni, Ascaris lumbricoides, Clonorchis sinensis, Echinococcus granulosus and Ancylostoma duodenale, as well as Pomacea canaliculata and Biomphalaria straminea snail tissues as the template DNA samples.

RESULTS

A fluorescent RAA assay was successfully established for nucleic acid detection of A. cantonensis, which achieved real-time amplification of the specific DNA fragment of A. cantonensis within 20 min at 37 ℃. By using the target gene fragment sequence-contained recombinant plasmids at various copy numbers and the genomic DNA from A. cantonensis as the DNA templates, the lowest detection limits of the fluorescent RAA assay were 10 copies/μL of recombinant plasmids and 100 pg/μL of genomic DNA, respectively. The fluorescent RAA assay was negative for detection of the genomic DNA from A. cantonensis, S. mansoni, A. lumbricoides, C. sinensis, E. granulosus, A. duodenale, and P. canaliculata and B. straminea snail tissues.

CONCLUSIONS

A simple, rapid fluorescent RAA assay has been successfully established, which has a high sensitivity and specificity for the nucleic acid detection of A. cantonensis.

Abstract 1048: Genomic analysis of patients with relapsed ovarian cancer enrolled in a phase II trial of nivolumab and bevacizumab

We analyzed genomic alterations in patients with relapsed ovarian cancer treated with combined nivolumab and bevacizumab in a phase II clinical trial, in order to identify potential biomarkers of response. Thirty-eight patients were treated with nivolumab and bevacizumab and the previously reported overall response rate was 28.9% (Liu et al, JAMA Oncology, 2019). Formalin-fixed paraffin-embedded patient tumor samples (acquired pre-treatment) underwent whole-exome sequencing, followed by quality control filtering and analysis of mutations, insertions/deletions, copy-number alterations, and mutational signatures using established methods. Differences in genomic event rates were assessed between response groups, as defined by presence or absence of objective response or clinical benefit. We describe the genomic alterations in all patients treated with nivolumab and bevacizumab, including several long-term responders with treatment duration &gt;24 months. The observed alterations in the patient cohort reflected known patterns of common mutations (e.g. TP53) and copy-number alterations (e.g. MYC amplification) in ovarian cancer. Within the limits of sample size, no significant differences in frequency of specific mutations were observed between response groups, with the possible exception of mutations in SETD1B, a histone methyltransferase, which were more frequent in the subset of patients lacking clinical benefit. BRCA1/2 mutation rate was similar between groups. Tumor mutational burden was not significantly different between groups. Initial exploratory analysis for copy-number alterations did not reveal genes with differential copy-number alterations between the response groups, and further analyses of copy-number alterations and mutational signatures are in progress. In summary, we describe genomic biomarker analysis from tumors of patients with relapsed ovarian cancer receiving treatment with nivolumab and bevacizumab. Taken together, we did not identify genomic alterations that clearly distinguish responding and non-responding patients in the data evaluated to date. Analysis of targeted RNA-sequencing data is planned as a next step. Further studies are needed to identify genomic or transcriptomic biomarkers of responses to checkpoint blockade and anti-angiogenic therapy in ovarian cancer.

Citation Format: Elizabeth H. Stover, Svitlana Tyekucheva, Yiwen Liu, Jennifer D. Curtis, Richard T. Penson, Joyce F. Liu. Genomic analysis of patients with relapsed ovarian cancer enrolled in a phase II trial of nivolumab and bevacizumab [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1048.

Abstract 4515: The anti-CD47 antibody SRF231 increases anti-tumor activity of standard of care chemotherapy in platinum-resistant PDX models of ovarian cancer

Background: CD47 is a type I integral membrane protein expressed on multiple human tumors, including ovarian cancer, and modulates cell processes such as cell migration, adhesion, T-cell function, and cell death via interaction with multiple ligands. Interaction of CD47 with SIRPα expressed on myeloid cells results in an inhibitory “don't eat me” signal that prevents phagocytosis of CD47-expressing cancer cells. Enhancement of the anti-tumor activity of chemotherapy has also been reported with CD47 antagonists. We investigated the effects of combining SRF231, an investigational fully human IgG4 antibody, with chemotherapy in models of human ovarian cancer.

Methods: Expression of CD47 in 8 established platinum-resistant PDX models of ovarian cancer was measured by immunohistochemistry with the anti-CD47 antibody SP279. SRF231-mediated phagocytosis of ovarian cancer cell lines was assessed using a macrophage coculture system. Cell death from combining SRF231 with either doxorubicin or platinum in vitro was assessed by Annexin V assay. The activity of SRF231 combined with doxorubicin in vivo was compared to isotype control, SRF231, or doxorubicin monotherapy in an ovarian cancer subcutaneous xenograft model, OVCAR3. Additionally, the activity of SRF231 combined with platinum was compared to isotype control, SRF231, or platinum monotherapy in two luciferase-expressing intraperitoneal PDX ovarian cancer models, as measured by bioluminescent imaging.

Results: CD47 expression was high across all 8 PDX models. SRF231 induced phagocytosis of ovarian cancer cell lines by human monocyte-derived macrophages. SRF231 potentiated doxorubicin- or oxaliplatin-mediated cell death in Jurkat cells in Annexin V assays. In the OVCAR3 xenograft model, the combination of SRF231 and doxorubicin resulted in significant tumor growth inhibition and improved survival compared to isotype control, SRF231 monotherapy, or doxorubicin monotherapy. In the PDX model DF216, which demonstrates no evidence of monotherapy response to SRF231, combination of SRF231 and carboplatin resulted in tumor regression with significantly enhanced anti-tumor activity compared to carboplatin or SRF231 monotherapy, as well as to isotype control. Similarly, in the PDX model DF86, where SRF231 demonstrates modest monotherapy activity, combination SRF231 and carboplatin resulted in tumor regression and significant increase in anti-tumor activity compared to carboplatin or SRF231 monotherapies.

Conclusion: Anti-CD47 directed therapy with SRF231, a fully human antibody, demonstrated the ability to significantly increase the anti-tumor activity of standard chemotherapies in xenograft and platinum-resistant PDX models of ovarian cancer. Further exploration of combining anti-CD47 and platinum regimens in ovarian cancer is warranted.

Citation Format: Joyce F. Liu, Kshama A. Doshi, Benjamin H. Lee, Marisa O. Peluso, Li Zhang, Shan Zhou, Qing Zeng, Stephen Wang, Paul T. Kirschmeier, Cam A. Tran, Cloud Paweletz, Matthew Rausch, Alison M. Paterson, Prafulla C. Gokhale, Ursula A. Matulonis. The anti-CD47 antibody SRF231 increases anti-tumor activity of standard of care chemotherapy in platinum-resistant PDX models of ovarian cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4515.

PARP Inhibitors in the Management of Ovarian Cancer: ASCO Guideline

PURPOSE

To provide recommendations on the use of poly(ADP-ribose) polymerase inhibitors (PARPis) for management of epithelial ovarian, tubal, or primary peritoneal cancer (EOC).

METHODS

Randomized, controlled, and open-labeled trials published from 2011 through 2020 were identified in a literature search. Guideline recommendations were based on the review of the evidence, US Food and Drug Administration approvals, and consensus when evidence was lacking.

RESULTS

The systematic review identified 17 eligible trials.

RECOMMENDATIONS

The guideline pertains to patients who are PARPi naïve. All patients with newly diagnosed, stage III-IV EOC whose disease is in complete or partial response to first-line, platinum-based chemotherapy with high-grade serous or endometrioid EOC should be offered PARPi maintenance therapy with niraparib. For patients with germline or somatic pathogenic or likely pathogenic variants in BRCA1 (g/sBRCA1) or BRCA2 (g/sBRCA2) genes should be treated with olaparib. The addition of olaparib to bevacizumab may be offered to patients with stage III-IV EOC with g/sBRCA1/2 and/or genomic instability and a partial or complete response to chemotherapy plus bevacizumab combination. Maintenance therapy (second line or more) with single-agent PARPi may be offered for patients with EOC who have not received a PARPi and have responded to platinum-based therapy regardless of BRCA mutation status. Treatment with a PARPi should be offered to patients with recurrent EOC that has not recurred within 6 months of platinum-based therapy, who have not received a PARPi and have a g/sBRCA1/2, or whose tumor demonstrates genomic instability. PARPis are not recommended for use in combination with chemotherapy, other targeted agents, or immune-oncology agents in the recurrent setting outside the context of a clinical trial. Recommendations for managing specific adverse events are presented. Data to support reuse of PARPis in any setting are needed.Additional information is available at www.asco.org/gynecologic-cancer-guidelines.

[Relationship of plasma vitamin A levels between neonates and pregnant women in third trimester]

OBJECTIVE

To study the correlation of plasma vitamin A (VitA) levels between neonates and pregnant women in third trimester.

METHODS

A total of 688 pregnant women were recruited in Yuanshi and Laoting counties of Hebei Province, from May to June 2009. Venous blood samples of women before delivery and cord blood samples of newborns were collected and measured for retinol (retinol concentration was used to reflect VitA level) using high performance liquid chromatography assay. According to venous blood plasma retinol concentration, maternal VitA nutritional status was divided into deficiency (<0.70 μmol/L), marginal deficiency (0.70-<1.05 μmol/L), and sufficiency (≥1.05 μmol/L). According to cord blood plasma retinol concentration, neonatal VitA nutritional status was divided into deficiency (<0.35 μmol/L), marginal deficiency (0.35-<0.70 μmol/L), and sufficiency (≥0.70 μmol/L); neonatal VitA relative deficiency was further defined as cord blood plasma retinol concentration lower than the 10th percentile. VitA placental transport ratio was defined as retinol concentration in the neonates divided by that in pregnant women. Multivariable fractional polynomials (MFP) model and Pearson correlation were used to study the dose-response relationship between maternal and neonatal plasma VitA levels, Logistic regression model to estimate the effect of maternal VitA nutritional status on neonatal VitA deficiency, and MFP model and Spearman correlation to describe the relationship between maternal VitA level and VitA placental transport ratio.

RESULTS

The average retinol concentration of the pregnant women was (1.15±0.30) μmol/L, and the prevalence of VitA deficiency and marginal deficiency were 4.5% and 37.8%, respectively. Average retinol concentration of the neonates was (0.78±0.13) μmol/L, and no neonates were VitA deficiency, 28.2% of the neonates were marginal deficiency. After multivariable adjustment, the VitA level of the neonates was positively and linearly related to maternal VitA level (p^m=1, P<0.05), with the corresponding Pearson correlation coefficient of 0.13 (P<0.01). As compared with the women with sufficient VitA, those with VitA deficiency (crude OR=2.20, 95%CI:1.04-4.66) and marginal deficiency (crude OR=1.43, 95%CI:1.01-2.02) had higher risks to deliver neonates with VitA marginal deficiency; while the risks turned to be non-significant after multivariable adjustment. The pregnant women with VitA deficiency had higher risk to deliver neonates with relative VitA deficiency before and after multivariable adjustment (crude OR=3.02, 95%CI:1.21-7.50; adjusted OR=2.76, 95%CI:1.05-7.22). The maternal VitA level was negatively and non-linearly correlated with placental transport ratio (p^m= -0.5, P<0.05), with corresponding adjusted Spearman correlation coefficient of -0.82 (P<0.001).

CONCLUSION

There was a positive linear dose-response relationship between VitA levels of newborns and pregnant women in third trimester, indicating that neonatal VitA storing levels at birth was affected by maternal VitA nutritional status.