Alpelisib-Induced Diabetic Ketoacidosis

Sodium-glucose cotransporter-2 inhibitors for hypergycemia in phosphoinositide 3-kinase pathway inhibition

PURPOSE

Phosphoinositide 3-kinase (PI3K) inhibition is used for the treatment of certain cancers, but can cause profound hyperglycemia and insulin resistance, for which sodium-glucose cotransporter-2 (SGLT2) inhibitors have been proposed as a preferred therapy. The objective of this research is to assess the effectiveness and safety of SGLT2 inhibitors for hyperglycemia in PI3K inhibition.

METHODS

We conducted a single-center retrospective review of adults initiating the PI3K inhibitor alpelisib. Exposure to different antidiabetic drugs and adverse events including diabetic ketoacidosis (DKA) were assessed through chart review. Plasma and point-of-care blood glucoses were extracted from the electronic medical record. Change in serum glucose and the rate of DKA on SGLT2 inhibitor versus other antidiabetic drugs were examined as co-primary outcomes.

RESULTS

We identified 103 patients meeting eligibility criteria with median follow-up of 92 days after starting alpelisib. When SGLT2 inhibitors were used to treat hyperglycemia, they were associated with a decrease in mean random glucose by -46 mg/dL (95% CI - 77 to - 15) in adjusted linear modeling. Five cases of DKA were identified, two occurring in patients on alpelisib plus SGLT2 inhibitor. Estimated incidence of DKA was: alpelisib plus SGLT2 inhibitor, 48 DKA cases per 100 patient-years (95% CI 6, 171); alpelisib with non-SGLT2 inhibitor antidiabetic drugs, 15 (95% CI 2, 53); alpelisib only, 4 (95% CI 0.1, 22).

CONCLUSIONS

SGLT2 inhibitors are effective treatments for hyperglycemia in the setting of PI3K inhibition.

Immune checkpoint inhibitor- and phosphatidylinositol-3-kinase inhibitor-related diabetes induced by antineoplastic drugs: two case reports and a literature review

Immune checkpoint inhibitor (ICI)- and phosphatidylinositol-3-kinase inhibitor (PI3Ki)-related diabetes mellitus are common side effects of anti-tumor drug use that present mainly as hyperglycemia. Here, we present two case reports of diabetes mellitus caused by the use of tremelimumab and apalutamide, respectively, in cancer treatment, and a comprehensive, comparative review of the literature on these forms of diabetes. Case 1 presented with diabetic ketoacidosis and was diagnosed with ICI-related diabetes mellitus and treated with insulin. Case 2 was diagnosed with PI3Ki-related diabetes mellitus, and her blood glucose level returned to normal with the use of metformin and dapagliflozin. We systematically searched the PubMed database for articles on ICI- and PI3Ki-related diabetes mellitus and characterized the differences in clinical features and treatment between these two forms of diabetes.

Sodium-Glucose Cotransporter-2 Inhibitors for Hyperglycemia in Phosphoinositide 3-kinase Pathway Inhibition

Purpose Phosphoinositide 3-kinase (PI3K) inhibition is used for the treatment of certain cancers, but can cause profound hyperglycemia and insulin resistance, for which sodium-glucose cotransporter-2 (SGLT2) inhibitors have been proposed as a preferred therapy. The objective of this research is to assess the effectiveness and safety of SGLT2 inhibitors for hyperglycemia in PI3K inhibition. Methods We conducted a single-center retrospective review of adults initiating the PI3k inhibitor alpelisib. Exposure to different antidiabetic drugs and adverse events including diabetic ketoacidosis (DKA) were assessed through chart review. Plasma and point-of-care blood glucoses were extracted from the electronic medical record. Change in serum glucose and the rate of DKA on SGLT2 inhibitor versus other antidiabetic drugs were examined as co-primary outcomes. Results We identified 103 patients meeting eligibility criteria with median follow-up of 85 days after starting alpelisib. When SGLT2 inhibitors were used to treat hyperglycemia, they were associated with a decrease in mean random glucose by -54 mg/dL (95% CI -99 to -8) in adjusted linear modeling. Five cases of DKA were identified, two occurring in patients on alpelisib plus SGLT2 inhibitor. Estimated incidence of DKA was: alpelisib plus SGLT2 inhibitor, 24 DKA cases per 100 patient-years (95% CI 6, 80); alpelisib with non-SGLT2 inhibitor antidiabetic drugs, 7 (95% CI 0.1, 34); alpelisib only, 4 (95% CI 0.1, 21). Conclusions SGLT2 inhibitors are effective treatments for hyperglycemia in the setting of PI3K inhibition, but given possible adverse events, SGLT2 inhibitors should be used with caution.

Ketoacidosis in a Patient with Type 2 Diabetes Requiring Alpelisib: Learnings and Observations Regarding Alpelisib Initiation and Rechallenge

Background

Diabetic ketoacidosis (DKA) is a rare complication of alpelisib, but cases of DKA are reported. Alpelisib's safety in patients with long-standing, suboptimally controlled diabetes is unclear since clinical trials of alpelisib did not include them.

Case

A case is presented on a patient with metastatic breast cancer and type 2 diabetes admitted for DKA eleven days after starting alpelisib. Since DKA is implicated in antihyperglycemics that inhibit sodium-glucose cotransporter-2 (SGLT2) inhibitors, her empagliflozin was discontinued. Alpelisib was also held since it was recently initiated. After the DKA resolved, she was discharged and restarted alpelisib. Within 4 hours of taking the first dose, the patient developed a second episode of DKA, and alpelisib treatment was stopped permanently.

Conclusion

Patients with long-standing type 2 diabetes are at high risk of alpelisib-induced Grade 3 and 4 hyperglycemia, including DKA. It is essential to communicate with non-oncology stakeholders about the risk of DKA with alpelisib as it can be overlooked for more common causes. Restarting alpelisib can result in severe hyperglycemia or DKA within 24 hours of the first dose. In this population, the risks associated with rechallenging alpelisib must be heavily weighed against its benefits. Before restarting alpelisib, a thorough evaluation of the appropriateness of the patient's antihyperglycemics and diet must occur to anticipate and mitigate a second event. Antihyperglycemics independent of the PI3K/AKT/mTOR pathway may be preferred agents. A plan should be in place to quickly respond to rising glycemia and early referral to a diabetologist or endocrinologist is recommended. Continuous glucose monitoring and hospital admission are recommended during rechallenge. A better understanding of alpelisib-induced hyperglycemia, especially in patients with diabetes, is required to navigate alpelisib treatment safely. Emphasis should be placed on patient education of symptoms and monitoring parameters.

Alpelisib-Induced Diabetic Ketoacidosis in a Patient With Metastatic Breast Cancer

We report the case of a 45-year-old woman with metastatic breast cancer who started treatment with alpelisib nine days before developing diabetic ketoacidosis (DKA). At the time of DKA diagnosis, blood tests showed a capillary blood glucose of 30 mmol/L, serum carbon dioxide level of 11 mmol/L, an anion gap of 25 mEq/L, and a glycated hemoglobin A1C (HbA1c) level of 6.4% (50 mmol/mol). Her HbA1C on admission was 5.6% (38 mmol/mol). Capillary blood glucose levels improved upon discontinuation of alpelisib and returned to baseline four days after drug discontinuation. DKA is a rare but serious adverse effect of alpelisib. Patients on this medication should be closely monitored for hyperglycemia and DKA. Further studies are needed to help identify patients at risk of hyperglycemia and DKA.

Alpelisib-Induced Diabetic Ketoacidosis in a Patient With Metastatic Breast Cancer

Alpelisib, a phosphatidylinositol-3-kinase (PI3K) inhibitor, is a new drug approved for metastatic breast cancer. Hyperglycemia is a known side effect of this medication, however diabetic ketoacidosis is rarely described. We are presenting a 64-year-old female with a known case of Type 2 diabetes mellitus (hemoglobin A1c [HbA1c] 5.6% ) controlled by metformin alone. She was also diagnosed with metastatic breast cancer. She received radiotherapy, trastuzumab and letrozole. Then, she was started on alpelisib as she failed other previous modalities. She presented to the emergency department with a two-week history of polyuria and polydipsia, and laboratory investigation results showed high anion gap metabolic acidosis, ketonemia, and hyperglycemia. She was treated for diabetic ketoacidosis (DKA). After the resolution of DKA, she was kept on daily insulin subcutaneous injections. She was restarted on a reduced dose of alpelisib, but despite this, her blood sugar readings continued to rise, requiring discontinuation of the medication with a resolution of hyperglycemia.

The goal of our case report is to emphasize the importance of close glucose monitoring when starting alpelisib to avoid serious complications like DKA.

How to inhibit breast cancer and breast cancer metastasis with Akt inhibitors: Lessons learned from studies in mice

The PI3K/Akt signaling pathway is frequently hyperactivated in different types of breast cancer. In the past two decades, major efforts have been made to develop inhibitors of this pathway to treat cancer patients. However, the most evolutionarily conserved function of this pathway is in cellular and organismal metabolism, which is hijacked by cancer cells. Thus, adverse metabolic consequences are expected when PI3K or Akt is targeted. These metabolic consequences, particularly hyperinsulinemia, could impede the efficacy of treatment. This review summarizes recent genetic studies in mice that could pave the way to efficient breast cancer and breast cancer metastasis treatment with Akt inhibitors.