stability of monoclonal antibody drugs on VAMS

An article by Hua Li et al at Boehringer Ingelheim Pharmaceuticals, Inc. in the United States published in the April 2021 edition of Bioanalysis, investigated the stability of two monoclonal antibodies (mAbs) under various conditions using Mitra^® microsampling devices with VAMS technology.

The paper is entitled “Whole blood stability evaluation of monoclonal antibody therapeutics using volumetric absorptive microsampling.” This mAbs study showed excellent stability of both trastuzumab and daclizumab even when the sampled Mitra devices had been stored at room temperature.

Diverse Applications of Monoclonal Antibody Therapies

Since the 1980s, there have been over 100 monoclonal antibody drugs approved for use in a variety of treatment areas. The monoclonal antibody therapies study described in the paper by Hua Li et al focuses on the application of two mAbs drugs.

The first drug is trastuzumab, which was developed to treat HER2 positive breast cancer. This type accounts for 20-30% of breast cancer and has the second worst prognosis for the disease. HER2 is an epidermal growth factor receptor and acts as a tyrosine kinase which plays a key function in the growth of cells.

It is often upregulated in cancers such as breast carcinoma. It is thought that trastuzumab has three mechanisms of action: HER2 internalization, antibody dependent cytotoxicity, and inhibition of specific pathways that increase cell cycle arrest and suppress cellular growth and proliferation.

The second mAbs drug discussed in the paper is daclizumab, which is used to treat Relapsing Multiple Sclerosis. Interestingly, daclizumab was originally developed to prevent transplant organ rejection and to treat severe uveitis and T cell leukemia.

This drug’s method of action is to block a critical part of the high-affinity interleukin-2 receptor (IL-2R). This, in turn, inhibits T cell activation as well as regulatory T cell survival and expansion, including activation-induced T-cell apoptosis (programmed cell death).

Use of Mitra Devices for Large Proteins

The research group at Boehringer Ingelheim Pharmaceuticals had previously published on both mAbs drugs (trastuzumab and daclizumab) after Hua Li et al successfully investigated these in a preclinical pharmacokinetic study. They had chosen to use Mitra devices with VAMS for that previous study as well due to its volumetric nature.

In the current paper the authors stated, “Mitra^® microsamplers stand out with their unique merits such as small volume requirements, accuracy, ease of use and elimination of cold chain shipping and biohazard costs.” They also said that because VAMS was a less invasive technology compared to standard wet sampling, it was preferred for vulnerable patients such as children and the elderly.

One observation that the group made was that although there had been a lot of Mitra microsampling studies investigating small molecules, there had been fewer focused on large molecules. For this reason, the group decided to conduct a follow-up study to investigate the stability of mAbs on Mitra devices and also extracts from the microsamples.

Study Methods and Findings

• The group used fresh EDTA stabilized rat blood to spike into both trastuzumab and daclizumab. They used a previously validated enzyme linked immunosorbent assay (ELISA) to measure the mAbs from the blood samples.
  
  
• Mitra samples (20 µL) were used to sample the blood in tubes where, upon drying, they were extracted into phosphate buffered saline prior to analysis.
  
  
• The group conducted five experiments:
  
  
  1. Recovery of mAbs from dried Mitra devices where the devices were sampled with 100 or 1000 ng/mL of either drug and then dried at room temperature in the dark for up to 480 h for daclizumab, and 216 h for trastuzumab. All samples for daclizumab were stable for around 300 h, and 96 h for trastuzumab.
     
     
  2. Recovery of mAbs from Mitra devices stored at -80 °C where devices were prepared in the same way as for experiment 1; they were dried at room temperature overnight in the dark, but then stored in the freezer. The sampled devices were then tested every two weeks. During this experiment, daclizumab was stable (within ±20% deviation) for up to 84 days and trastuzumab showed a similar stability duration at up to 91 days.
     
     
  3. Stability of extractions from Mitra devices stored at -80 °C. Mitra devices were prepared as for experiment 1 but instead of the devices stored at -80 °C, the final extracts were. Results showed the extracts were within ±20% deviation for the same durations as experiment 2.
     
     
  4. Evaluation of the recovery of daclizumab stored at room temperature in dark vs light and measured at 96, 240, 336 and 480 hours. No difference was seen between these conditions. Due to issues encountered during the COVID-19 Pandemic, the same experiment was not conducted with trastuzumab.
     
     
  5. Evaluation extraction recovery rate of daclizumab stored for 480 h in both dark and light conditions at room temperature in different extraction. The research group saw no difference in extracting at room temperature vs 37 °C. When dried in light conditions, extraction time did make a difference where a negative bias was seen at 4 hours compared to 1-3 hours. Extraction time did not affect those sampled devices that had been stored in the dark.

Study Authors’ Conclusions

• Mitra devices with VAMS could be used for large therapeutic remote sampling at room temperature without refrigeration or freezing, which would save money and time. Furthermore, sampling with these devices could be conducted by the layperson at home.
  
  
• The results were similar to a related the study conducted by Bloem K (summarized in a previous blog).
  
  
• VAMS samples could be stored for a long time frozen at -80 °C.
  
  
• For daclizumab, the microsamples did not need to be protected from light. NB trastuzumab was not tested in this experiment.
  
  
• For daclizumab, extraction times should not be longer than 3 hours.

Neoteryx Comments

This thorough investigation into extraction stability demonstrated how stable monoclonal antibodies, or mAbs, are in dried blood microsamples collected on microsampling tools such as the Mitra^® device. It is likely that the hemaPEN^® device with its volumetric sampling approach would also produce similar results.

It is always critical to conduct stability experiments which mimic the journey of the sample when validating methods, but certainly this and other studies show that antibodies (that have been tested) show sufficient stability for remote sampling applications.

This article was summarized for our readers by James Rudge, PhD, Neoteryx Technical Director. This is curated content. To learn more about the important research outlined in this blog, visit the original article in Bioanalysis. 

For more information on how Neoteryx microsampling products from Trajan help researchers, visit our Technical Resource Library.

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