Endocrinopatías autoinmunitarias inducidas por anticuerpos inmunomoduladores en el tratamiento del cáncer

Replacement Dose for Overt Hypothyroidism Induced by Programmed Cell Death Protein 1 Antibodies May Be Higher than Recommended

BACKGROUND

The present recommendations, consensus, or guidelines for the replacement dosage for hypothyroidism induced by programmed cell death protein 1 (PD-1) therapy are not uniform, and there are very few special clinical trials that have examined the replacement dosage for it.

OBJECTIVES

This article illustrates the clinical characteristics of hypothyroidism induced by PD-1 antibodies (Abs) and reports the recommended replacement dosage for hypothyroidism.

METHODS

Eighteen patients with overt primary hypothyroidism induced by PD-1 Abs (group 1) were selected from 655 patients with different tumor types. Retrospective analysis was performed on patients in group 1 and 18 patients with natural courses of overt primary hypothyroidism who were age- and sex-matched with the patients in group 1 (group 2). The replacement dosages required for the patients in the two groups were compared.

RESULTS

Thyroid dysfunction occurred in group 1 after approximately 3.0 ± 1.4 cycles of PD-1 therapy (1-6 stages), with a median time of 61.5 days. The median time of onset of hypothyroidism among all patients was 87.5 days (30-240 days). Most of the patients with hypothyroidism were asymptomatic, and the onset of hypothyroidism was independent of age, sex, TPOAb, TgAb and TSH in group 1 (P>0.05). The average replacement dosage for patients in group 1 was 1.8 ± 0.6 μg/kg/d (0.6-3.2 μg/kg/d). Multiple linear regression analysis showed that sex, age, TPOAb, TgAb and TSH were not correlated with drug dosage.

CONCLUSION

It seemed that the average maintenance dosage of levothyroxine might need to be 1.8 μg/kg/day for patients with overt hypothyroidism induced by PD-1 Abs.

Controversies on the possible role of immune checkpoint inhibitors in pediatric cancers: balancing irAEs and efficacy

Pediatric cancers are not the equivalent of adult cancers occurring at a younger age and the prospect of immunotherapy in children has not been received with the same enthusiasm as in the adult setting. Although most pediatric malignancies are considered immunologically cold, we are learning more about PD-L1 expression, tumor mutational burden, and microsatellite instability in several pediatric cancers. The side effects of immunotherapy are an important consideration. Immune checkpoint inhibitors (ICIs) engender a unique constellation of inflammatory toxicities known as immune-related adverse events (irAEs). Three early-phase trials-KEYNOTE-051, iMATRIX, and ADVL1412-were the first to describe irAEs in pediatric patients and ICIs were well tolerated. There was concern about unknown late irAEs in pediatric patients, as they have much more time to develop than in adult or elderly patients. Academic clinicians, biopharmaceutical companies, and parents' advocates concluded that no benefit could be expected from further monotherapy trials employing other ICIs with the same mechanism of action until more scientific knowledge becomes available. On the other hand, ICIs could be useful in combination with other therapies to prevent the functional inactivation of several pathways in the hostile microenvironment. Future clinical studies on ICIs in children need to build on strong biological premises, taking into account the distinctive immunobiology of pediatric cancers vis-à-vis ICI-responsive adult cancers. We need to gain and share experiences of new therapies for managing pediatric patients with cancer, clarifying to what extent we can extrapolate the data obtained in adults.

Isolated ACTH deficiency induced by cancer immunotherapy: a systematic review

Immunotherapy with immune checkpoint inhibitor (ICI) monoclonal antibodies has shown to be an effective therapeutic alternative in several malignant tumors. However, adverse effects related to an activation of the immune system may accompany ICI therapy. Among the immune-related adverse events (irAEs) are autoimmune endocrine adverse effects, such as thyroiditis, and hypophysitis. Secondary adrenal insufficiency due to isolated ACTH deficiency (IAD) has also been recently reported to be associated with ICI antibodies. We carried out a systematic review of IAD cases induced by cancer immunotherapy published to date using PubMed's database. We selected 35 articles that reported 60 cancer patients diagnosed with IAD induced by ICI therapy. The prevalence was higher in men (ratio 1.6/1). Mean age at diagnosis was 63.2 ± 11.6 (range,30-87). Melanoma was the tumor most commonly reported (35%) followed by lung (28.3%) and kidney cancer (18.3%). The ICI monoclonal antibody most frequently associated was nivolumab in monotherapy (60%), followed by pembrolizumab (18.3%). Median (IQR) time to develop IAD after starting ICI therapy was 6 (4-8) months. The main symptoms at IAD diagnosis were fatigue (82.8%) and anorexia (67.2%). Hyponatremia (68%) and eosinophilia (31.8%) were the laboratory abnormalities most frequently associated with IAD. Pituitary magnetic resonance imaging (MRI) was normal in most patients (93%). Thyroiditis was the most prevalent (35%) endocrine irAE associated with IAD. In conclusion, ICI-induced IAD is a rare and potentially life-threatening condition that must be taken into account whenever treatment with immunotherapy in cancer patients is started due to their potential serious prognostic implications.

Thyroiditis and immune check point inhibitors: the post-marketing experience using the French National Pharmacovigilance database

Immunotherapy with immune checkpoint inhibitors (ICIs) for cancer has become increasingly prescribed in recent years. Indeed, it is used to treat both solid and hematological malignancies due to their considerable potential in treating melanoma, non-small cell lung and other cancers. Immune-mediated related adverse endocrine toxicity, and especially thyroiditis, is seen as a growing problem needing specific screening and management. This study aims at describing thyroid dysfunctions induced by the ICIs marketed in France, which are registered in the French Pharmacovigilance database. This database was queried for nivolumab, pembrolizumab, and ipilimumab-induced adverse drug reactions reported before April 30, 2017. Both a pharmacologist and an endocrinologist have reviewed each case to select only those of peripheral thyroiditis (thyrotoxicosis and hypothyroidism). During this period, 110 thyroiditis following ICI therapy were reported. Sex/ratio was around one. Most of the cases (47.2%) were asymptomatic. Although some thyrotoxicosis cases were severe, no orbitopathy was reported. Hypothyroidism and thyrotoxicosis were equally described. Antithyroid antibodies were positive in only 16% patients. The ultrasonography was informative in 19% patients. Levothyroxine supplementation was necessary in 57% patients, leading to 19% recovery. With a dedicated optimized management, most of the cases did not require immunotherapy discontinuation. Finally, immune-mediated related thyroiditis is increasing due to a wider prescription of ICI therapy in various cancer conditions and systematic screening. Often asymptomatic, they lead to a local activation accompanied by hormonal deficiency in the long run. It is necessary to carry out an early and sustained multidisciplinary screening to allow immunotherapy continuation.

Cancer immunotherapy-induced endocrinopathies: Clinical behavior and therapeutic approach

Cancer immunotherapy has proven to be effective in a wide variety of tumors. The use of immune checkpoint blocking monoclonal antibodies has become a standard treatment regimen in some of them as advanced melanoma. However, given the mechanism of action, its use may be associated with immune-related adverse events that may complicate the clinical course and prognosis of patients. Among these are autoimmune endocrine adverse effects, such as hypophysitis, hypo and hyperthyroidism, and adrenal insufficiency. This review focuses on the most relevant and new aspects related to the incidence, clinical presentation, diagnosis and treatment of these adverse effects associated with different types of immune checkpoint inhibitors in cancer immunotherapy.

Limitations and opportunities for immune checkpoint inhibitors in pediatric malignancies

Immune checkpoint inhibitors (ICI) have shown great promise in a wide spectrum of adult solid and hematological malignancies, achieving objective tumor responses and prolonging survival. However, there is limited clinical success amongst pediatric patients. In this review, we summarize the current understanding of ICI and present an up-to-date overview of recent and ongoing clinical trials of ICI in pediatric malignancies. In addition, we will discuss immunologic and clinical difficulties in this young population, as well as future prospects for combination of ICI with other immune-based and conventional treatments.