Ado-Trastuzumab Emtansine-Induced Pulmonary Toxicity: A Single-Institution Retrospective Review

Trastuzumab-Induced Interstitial Pneumonitis

Trastuzumab is a recombinant immunoglobulin G1 monoclonal antibody used to treat human epidermal growth factor receptor 2 (HER2) cancers. Trastuzumab-induced interstitial pneumonitis is a rare adverse effect reported in a few patients. Interstitial pneumonitis presents as symptoms of dyspnea, hypoxia, cough, and fever. If the patient is treated early, corticosteroids can slow or reverse the disease progression. A 41-year-old woman presented with dyspnea and a dry cough three weeks after her third cycle of trastuzumab therapy for breast cancer. A diagnosis of trastuzumab-induced interstitial pneumonitis was made after multiple other disease processes were ruled out. The patient was started on methylprednisolone while inpatient and transitioned to prednisone for outpatient therapy. The patient was maintained on 2-3L of oxygen throughout her hospital stay and was discharged on 3L of oxygen through nasal cannula. Trastuzumab was never restarted after discharge. There have been many trials evaluating the safety, efficacy, and optimal treatment regimen of trastuzumab, but there are only a few reports of interstitial pneumonitis adverse reaction. The lack of correlation and limited cases make this adverse effect very difficult to diagnose and monitor. New trials and case reports can bring an insight into contributing factors, symptoms at onset, and treatment for future patients. With the increase in use of trastuzumab therapy, physicians should be aware of how to diagnose and treat the rare adverse reaction of trastuzumab-induced interstitial pneumonitis.

Phase I Trial of a Novel Anti-HER2 Antibody-Drug Conjugate, ARX788, for the Treatment of HER2-Positive Metastatic Breast Cancer

PURPOSE

ARX788 is a novel antibody-drug conjugate (ADC) comprised of an anti-HER2 mAb and a potent tubulin inhibitor payload AS269 that is site-specifically conjugated to the antibody via a nonnatural amino acid incorporated into the antibody. Herein, we present the results of a phase I study of the safety, pharmacokinetics, and antitumor activity of ARX788 in patients with HER2-positive metastatic breast cancer (MBC).

PATIENTS AND METHODS

Patients with HER2-positive MBC received ARX788 at doses of 0.33, 0.66, 0.88, 1.1, 1.3, or 1.5 mg/kg every 3 weeks, or 0.88, 1.1, or 1.3 mg/kg every 4 weeks. The dose-limiting toxicity (DLT) was assessed for 84 days for pulmonary toxicity and at a duration of one cycle (21 or 28 days) for other toxicities.

RESULTS

In total, 69 patients were enrolled. No DLT or drug-related deaths occurred. Most patients (67/69; 97.1%) experienced at least one treatment-related adverse event (TRAE). Common (≥ 30%) TRAEs included an increase in aspartate aminotransferase, an increase in alanine aminotransferase, corneal epitheliopathy, alopecia, hypokalemia, interstitial lung disease (ILD)/pneumonitis, and an increase in aldosterone. While 34.8% of participants experienced ILD/pneumonitis, only 2 had a severity of grade 3. At 1.5 mg/kg every 3 weeks, the recommended phase II dose, the objective response rate was 65.5% [19/29, 95% confidence interval (CI), 45.7-82.1], the disease control rate was 100% (95% CI, 81.2-100), and the median progression-free survival was 17.02 months (95% CI, 10.09-not reached).

CONCLUSIONS

ARX788 demonstrated a manageable safety profile with promising preliminary signs of activity in patients with HER2-positive MBC who progressed on prior anti-HER2 therapies.

Comparison of Anticancer Drug Toxicities: Paradigm Shift in Adverse Effect Profile

The inception of cancer treatment with chemotherapeutics began in the 1940s with nitrogen mustards that were initially employed as weapons in World War II. Since then, treatment options for different malignancies have evolved over the period of last seventy years. Until the late 1990s, all the chemotherapeutic agents were small molecule chemicals with a highly nonspecific and severe toxicity spectrum. With the landmark approval of rituximab in 1997, a new horizon has opened up for numerous therapeutic antibodies in solid and hematological cancers. Although this transition to large molecules improved the survival and quality of life of cancer patients, this has also coincided with the change in adverse effect patterns. Typically, the anticancer agents are fraught with multifarious adverse effects that negatively impact different organs of cancer patients, which ultimately aggravate their sufferings. In contrast to the small molecules, anticancer antibodies are more targeted toward cancer signaling pathways and exhibit fewer side effects than traditional small molecule chemotherapy treatments. Nevertheless, the interference with the immune system triggers serious inflammation- and infection-related adverse effects. The differences in drug disposition and interaction with human basal pathways contribute to this paradigm shift in adverse effect profile. It is critical that healthcare team members gain a thorough insight of the adverse effect differences between the agents discovered during the last twenty-five years and before. In this review, we summarized the general mechanisms and adverse effects of small and large molecule anticancer drugs that would further our understanding on the toxicity patterns of chemotherapeutic regimens.

Pneumonitis associated with Trastuzumab emtansine in a patient with metastatic breast cancer

INTRODUCTION

Trastuzumab emtansine (TDM-1) is an antibody-drug conjugate effective in human epidermal growth factor receptor-2 - expressing advanced breast cancer. Pulmonary complications of TDM-1 are rarely reported. TDM-1-associated interstitial lung disease is referred to as pneumonitis.

CASE REPORT

A 47-year-old female patient who underwent modified radical mastectomy and axillary lymph node dissection operations due to a palpable mass in the right breast and axillary region. The patient who had received multiple chemotherapy was last receiving TDM-1 treatment. Fatigue, dyspnea, and tachypnea were detected for the first time on 20 days after the 6^th treatment.

MENAGEMENT AND OUTCOME

In our case, we first considered metastasis, pneumonia and fungal infection based on radiological findings, but the lack of response to the treatments and the results of the investigations suggested drug-induced pneumonia and steroid treatment was started. Our case had a complete radiological recovery and complete response to sterod therapy. In such cases, it is important to first exclude infections and metastasis. In cases of drug-induced pneumonia, the first treatment option is systemic corticosteroids and generally responded well.

DISCUSSION

Unlike other cases of interstitial pneumonia, lung imaging of our case was resembling a metastasis, pneumonia and fungal infection. With increasing use of TDM-1, we will have more experience in both efficacy and complications of TDM-1. Although TDM-1 is a well-tolerated drug, clinicians should be aware of rare pulmonary complications and prepared to respond appropriately.

Acute eosinophilic pneumonia: a fatal reaction to ado-trastuzumab

Ado-trastuzumab emtansine (T-DM1) is a monoclonal antibody drug conjugate approved for the treatment of HER2-positive breast cancers. Presented here is a case report of a patient who developed fatal pulmonary toxicity in the form of acute eosinophilic pneumonia while undergoing treatment with T-DM1. Prior to beginning T-DM1 therapy, this patient had been treated with two HER2-targeted agents (trastuzumab, pertuzumab) per National Comprehensive Cancer Network (NCCN) guidelines. This case represents a novel presentation of toxicity associated with T-DM1 while perhaps demonstrating additive toxicity associated with multiple lines of HER2 targeted therapies.

A Review of Treatment-Induced Pulmonary Toxicity in Breast Cancer

This article reviews the available literature that describes the incidence, diagnosis, mechanism, symptoms, and management of pulmonary toxicity induced by radiation therapy and current systemic medications used to treat breast cancer. An extensive literature search was conducted via Ovid Medline to identify all potentially relevant articles written in English from 2010 through January 2020. Additional relevant articles outside the time frame were included as needed. Although the risk of pulmonary toxicity from various breast cancer treatments is small in most instances, it can be fatal. Due to the high prevalence of breast cancer and the range of treatment options, healthcare providers should be aware of the risk of pulmonary toxicity from those treatments and how to prevent or manage complications.

Risk Minimization of Antibody-Drug Conjugates in Oncology: A Review

Antibody-drug conjugates (ADCs) are new treatment options for certain cancers, especially those in advanced states with limited treatment options. Their unique design provides targeted therapy with toxins that otherwise would not be available, but they manifest toxicities that require risk minimization interventions to optimize their tolerability. We summarize selected toxicities for ADCs that have been approved through the end of 2020 and three investigational ADCs, which include both payload and linker, as described in the US Prescribing Information, the European Summary of Product Characteristics, and study protocols. These toxicities include peripheral neuropathy; pulmonary, skin, hepatic, and ocular toxicities; hyperglycemia; left ventricular dysfunction; and fluid-related events. We also review the risk minimization approaches to managing these toxicities as described in the product labels and study protocols. Our general observation suggests that the selected toxicities of the approved ADCs are primarily associated with off-target effects of the drug payloads. We also observed that the risk minimization approaches used to manage the selected toxicities are similar across product labels and study protocols. ADCs provide a unique treatment approach that is currently focused on advanced or refractory cancers. The risk minimization approaches for the selected toxicities for the approved ADCs per product label, or the study protocol for those in clinical investigation, are similar to those of standard chemotherapy agents and other pharmaceutical agents for the treatment of advanced malignancies. These risk minimization measures align with standard medical practice and are likely familiar to and feasible for physicians who prescribe for, and to other healthcare practitioners who care for, patients treated with ADCs.

A Phase II Study of Telisotuzumab Vedotin in Patients With c-MET-positive Stage IV or Recurrent Squamous Cell Lung Cancer (LUNG-MAP Sub-study S1400K, NCT03574753)

INTRODUCTION

Lung-MAP S1400K was designed to evaluate the response to telisotuzumab vedotin, an antibody-drug conjugate targeting c-MET, in patients with c-MET-positive squamous cell carcinoma (SCC).

PATIENTS AND METHODS

Patients with previously treated SCC with c-MET-positive tumors (H score ≥ 150, Ventana SP44 assay) were enrolled into 2 cohorts: Cohort 1 (immune checkpoint inhibitor-naive) and Cohort 2 (immune checkpoint inhibitor refractory). Telisotuzumab vedotin 2.7 mg/kg was administered intravenously every 3 weeks until disease progression or unacceptable toxicity. Response assessments were performed every 6 weeks. The primary endpoint was response by Response Evaluation Criteria in Solid Tumors (RECIST) v1.1. Secondary endpoints included progression-free survival, overall survival, response within cohort, duration of response, and toxicities. Interim analysis was planned after 20 evaluable patients, with ≥ 3 responses needed to continue enrollment.

RESULTS

Forty-nine patients (14% of screened patients) were assigned to S1400K, 28 patients enrolled (15 in Cohort 1 and 13 in Cohort 2), and 23 were eligible. S1400K closed on December 21, 2018 owing to lack of efficacy. Two responses (response rate of 9%; 95% confidence interval, 0%-20%) were reported in cohort 1 (1 complete and 1 unconfirmed partial response), whereas 10 patients had stable disease, with a disease control rate of 52%. The median overall and progression-free survival was 5.6 and 2.4 months, respectively. There were 3 grade 5 events (2 pneumonitis, in Cohort 2, and 1 bronchopulmonary hemorrhage, in Cohort 1).

CONCLUSION

Telisotuzumab vedotin failed to meet the pre-specified response needed to justify continuing enrollment to S1400K. Pneumonitis was an unanticipated toxicity observed in patients with SCC.

Trastuzumab Deruxtecan (DS-8201a): The Latest Research and Advances in Breast Cancer

The development of antibody-drug conjugates composed of a cytotoxic agent and a monoclonal antibody carrier offers an important alternative to classic chemotherapy strategies. Trastuzumab deruxtecan (DS-8201a) is a next-generation antibody-drug conjugate composed of a monoclonal anti-HER2 antibody and a topoisomerase I inhibitor, an exatecan derivative (DX-8951f). DS-8201a resulted in favorable outcomes in HER2-positive heavily pretreated breast cancer patients and also had a promising efficacy in patients with HER2-negative/low-expressing disease, whose options are limited. Interestingly, a recently published phase 2 trial (NCT03248492) reported 60% overall response and 97% disease control in patients with HER2-positive disease previously treated with multiple regimens, including trastuzumab emtansine. On the basis of recent clinical trials, the US Food and Drug Administration granted accelerated approval to DS-8201a in advanced or unresectable HER2-positive breast cancer pretreated with at least two HER2-targeting treatment lines. We review all preclinical and clinical data of DS-8201a regarding breast cancer.

ADC Analysis by Hydrophobic Interaction Chromatography

Hydrophobic interaction chromatography (HIC) is a traditional technique used for the separation, purification, and characterization of proteins. As the number of antibody-drug conjugates (ADCs) continues to increase in clinical trials, HIC and other orthogonal methods utilizing changes in hydrophobicity are being used for ADC characterization and analysis. Unlike other techniques, HIC uniquely allows for protein analysis under mild nondenaturing conditions that preserve the native structure and activity of the molecules. Analysis of the ADC in its native form is advantageous. Herein, we describe a generic HIC protocol for the screening, analysis, and characterization of ADCs using an ammonium sulfate buffer and a high-pressure liquid chromatography system. Parameters affecting data quality and interpretation are addressed. In addition, several recommendations are included for method optimization and troubleshooting.