Literature is scarce regarding the use of clopidogrel during pregnancy and the potential hazard to maternal and fetal health. We report a 33-year-old female, who presented to our clinic at 40 weeks gestation with a history of multiple prior ischemic strokes and transient ischemic attacks. The patient was placed on clopidogrel for secondary stroke prophylaxis prior to conception and maintained therapy throughout pregnancy without interruption or complication. Clopidogrel was discontinued 7 days prior to induction of labor, and a healthy baby was vaginally delivered without bleeding complications or congenital anomalies. Clopidogrel was restarted 12 hours postpartum without an incident. To our knowledge, this is the first report of clopidogrel use in pregnancy for secondary stroke prophylaxis. We also provide a current review of the literature of the use of clopidogrel in pregnancy. Based on the limited data available, clopidogrel use in pregnancy has not demonstrated significant toxicity to either the mother or the newborn. However, additional studies are needed to further assess the efficacy and safety of this medication in this patient population.

Background: Heparin-induced thrombocytopenia (HIT) is a drug-induced, immune-mediated prothrombotic disorder associated with thrombocytopenia and venous and/or arterial thrombosis.Up to 5% of patients exposed to heparin for at least one week develop HIT, and approximately 50% of them will have thrombosis. Diagnosis of HIT is suspected from the clinical picture based on the ''4 T's'' (Thrombocytopenia, Timing, Thrombosis, no other cause of platelet fall) or the HIT Expert Probability (HEP) scoring system. However, often these "4 T's" are ignored and testing is inappropriately ordered in low risk patients. This could lead to possible morbidity and increase length of hospital stay. We opted to look back at the appropriateness of testing done within our academic center. Methods/ Design: All hospitalized patients with thrombocytopenia who underwent HIT antibody testing (HIT ELISA) during February 2013 were screened using our internal electronic medical record. Patients were subdivided to low, intermediate or high pretest probability group according to the 4Ts scoring system. Appropriateness of testing was determined according ASH 2013 Clinical Practice Guideline on the Evaluation and Management of Adults with Suspected Heparin-Induced Thrombocytopenia (HIT). HIT Ab test is recommended to be tested when there is intermittent to high probability of HIT (4T's score above or equal to 4). The percentage of appropriate/inappropriate testing was calculated. The results were then subdivided by ordering physician group. Results: 120 HIT ab tests were performed during February 2013 in our institution. Only 13 patients tested had a positive HIT Ab. Internal medicine ordered the majority of these tests. Of the 120 patients tested, 7 patients had high risk and another 50 had intermediate risk as per 4T's scoring. 61 patients were low risk and should not have been tested. (Table 1) Table 1. HIT antibody test ordered per Service and probability of HIT. Service ordering test Low probability of HIT Intermediate/high probability of HIT TOTAL Internal Medicine 28 28 56 Cardiothoracic Surgery 13 11 24 Hematology Oncology 7 5 12 Cardiology 3 1 4 Surgery 1 4 5 Emergency medicine 0 1 1 Infectious disease 4 0 4 Pulmonary 0 1 1 Critical care 1 6 7 Nephrology 1 2 3 Ob Gyn 1 0 1 Family Medicine 2 0 2 TOTAL 61 59 120 Conclusions: HIT testing has been overused within our institution. Low platelets, without other signs or symptoms of typical HIT were used as a trigger for testing the antibody. This has potential to cause harm due to increased bleeding risk, increased length of hospital stay, and the potential to utilize extended anticoagulation when not necessary. Better education on the appropriateness of the test can limit the potential harm of its use. Disclosures No relevant conflicts of interest to declare.

Background: Pertuzumab, a monoclonal antibody targeting subdomain II of HER2 and blocking dimerization, was approved by the FDA in 2013 as neoadjuvant therapy in combination with trastuzumab + chemotherapy for HER2+ locally advanced or early-stage breast cancer patients (pts). TCHP (Docetaxel/Carboplatin/Trastuzumab/Pertuzumab) is a popular, non-anthracycline neoadjuvant therapy. In the TRYPHAENA trial, pathologic complete response (pCR) rate was 63.6% with 6 cycles of neoadjuvant TCHP (47.5% in ER+/PR+ and 81.1% in ER-/PR- tumors). We previously reported (SABCS 2015) our institutional experience with neoadjuvant TCHP in 75 pts with operable/locally advanced HER2+ breast cancer (10/2013 - 12/2015). Now we report our updated experience of 230 pts (10/2013 - 12/2019) with neoadjuvant chemotherapy + dual anti-HER2 therapy. Patients & Methods: Medical record search identified HER2+ pts (T1c-T3/N0-3 or Tany/N1-3) treated with neoadjuvant chemotherapy + dual anti-HER2 therapy from 10/2013 to 12/2019. Collected information included pt and tumor characteristics at diagnosis, details of neoadjuvant therapy, clinical, radiologic, & pathologic assessment of tumor response, type of breast and axillary nodal surgery, and long-term disease outcomes. Results: 230 pts (229 female, 1 male) met the inclusion criteria; median age: 52 yrs (range 25-79); Clinical stage: I (2%), II (78%) , III (20%); ER+ and/or PR+ 70% ; ER-/PR- 30%. 228 pts received TCHP and 2 pts AC then THP. 170 pts (74%) received 6 cycles of TCHP without dose reduction; 49 pts (21%) received 6 cycles, but with dose reduction (most commonly due to diarrhea, nausea, neutropenia, and anemia); 11 pts (5%) received < 6 cycles (7 of those also needed dose reduction). Mean left ventricular ejection fraction was 62.0% pre-treatment, and 60.9% post-treatment. Of the 230 pts who underwent breast surgery (1 had no breast primary at presentation), 86 pts (38%) had breast conserving surgery, 19 (8%) unilateral mastectomy, and 124 (54%) bilateral mastectomy. Axillary assessment was by SLNB in 75% and ALND in 25% (with/without SLNB). Among 138 pts with cN0 and axillary assessment, 124 had SLNB (4 had + nodes), 14 had ALND (11 had + nodes). Among 91 pts with cN1-3, 47 had SLNB (1 had + nodes) and 44 had ALND (27 had + nodes). Overall pCR rate (ypT0/Tis, ypN0) was 59%. pCR rate was 50% for ER+ and/or PR+, and 79% for ER-/PR-. pCR by Stage: I (50%), II (60%), III (55%). At median follow-up of 2.9 years, 221 pts (96%) were alive with no evidence of disease; 8 pts (3.5%) have experienced recurrence (6 distant, 1 locoregional, 1 unknown site), and 1 pt died after developing AML as the only event. The table below presents details on the 8 pts who suffered recurrence: 4 had clinical stage II disease, and 4 clinical stage III. All pts had hormone receptor + tumors at diagnosis. 7 of 8 pts (88%) with recurrence did not have pCR at surgery. Most common sites of distant metastases as first event were liver and bone. Of the 8 pts with recurrence, 6 are alive with disease (median follow-up 2.8 years). There was 1 death due to disease progression, and 1 pt was lost to follow-up. Conclusions: Our updated results continue to demonstrate the clinical safety and efficacy of neoadjuvant therapy with TCHP for operable/locally advanced HER2+ breast cancer. Our pCR rates are similar to those observed in the TRYPHAENA trial. Longer follow-up is required to evaluate the long-term clinical outcomes with this regimen. Recurrence DataPatient NumberAge at DiagnosisDate of DiagnosisHormone Receptor at DiagnosisClinical Stage at DiagnosisType of Breast SurgerypCRPathologic Stage at SurgeryDate of RecurrenceTime to Metastases (Years)Site of Recurrence16511/19/14PositivecT2N1 (IIB)Left MastectomyYesypT0N0 (0)4/6/172.4Liver, Bone2366/15/15PositivecT2N0 (IIA)Bilateral MastectomyNoypT3N0 (IIB)3/19/182.8Liver3546/29/15PositivecT2N3 (IIIC)Left MastectomyNoypT1bN1a (IIA)10/2/194.3Bone4577/1/15PositivecT2N3 (IIIC)Left LumpectomyNoypT1cN1a (IIA)2/4/193.6Bone, Soft Tissue5568/20/15PositivecT2N0 (IIA)Left LumpectomyNoypT1aN0 (IA)6/28/182.8Lymph Node6264/29/16PositivecT4N0 (IIIB)Bilateral MastectomyNoypT2N1 (IIB)12/13/171.6Liver7539/27/16PositivecT3N3 (IIIC)Bilateral MastectomyNoypT3N3 (IIIC)Not KnownNot KnownNot Known8319/3/17PositivecT2N1 (IIB)Bilateral MastectomyNo (clinical progression)ypT3N2a (IIIC)6/25/180.8Lungs Citation Format: Nirja Shah, Nikita Shah, Said Baidas, Ana Cuesta-Fernandez, Marc Demers, Maria Demori, Tomas Dvorak, Rachel Eisenberg, Terrence Gross, Danielle Henry, Michael Kahky, Patrick Kelly, Swathy Kolli, Regan Rostorfer, Jeffrey Smith, Cameron Swanick, Eleftherios Mamounas. Clinical outcomes with neoadjuvant chemotherapy plus dual anti-HER2 therapy in patients with operable/locally advanced breast cancer: Single institution experience [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS10-42.