Over the years, Charles River has developed formulations for many proteins and other large molecules for different routes of administration, including intravenous, intraperitoneal, intramuscular, subcutaneous, and ocular. Our formulation team has the expertise and capabilities to work on complex formulations which, once developed, can be easily handed off to the manufacturing team of choice for scale-up. Our capabilities include:

  • Modeling to determine hydrophobicity and higher order structure predictions
  • Evaluation of solubility properties in various conditions (e.g., pH, salts, detergents)
  • Protein concentration and aggregation determination
  • Stability determination
  • Stability chambers from -80˚C up to 60˚C with controlled humidity
  • High-throughput stability screening using ITF/ETF with temperature modulation
  • Forced degradation studies
  • Accelerated stability studies
  • Photostability testing
  • Assessment of accelerated stability studies for determination of optimal formulation
  • Lyophilization cycle development
  • Pilot-scale lyophilization

Our Approach

Our approach in protein formulation consists of conducting a series of pre-formulation trials to establish product solubility in various pH conditions and ionic strengths and also its solubility in salts and other excipients, which may include detergents and protein stabilizing agents. Once the solubility properties have been established, a new iteration to finely tune pH conditions, buffering agents, ionic strengths and salts, along with stabilizing detergents and other excipients is conducted. To aid in selecting the optimal conditions, a high-throughput stability screening approach is performed using a proprietary formulation development technique. Other stability-indicating techniques are then used along with appropriately designed stress studies for final formulation selection.

We have also developed a proprietary screening method for rapid evaluation of protein aggregation propensity, upon exposure to various formulation conditions. When combined with a statistical analysis approach, such as design-of-experiment (DOE), the obtained results are highly predictive of protein stability for both liquid and lyophilized formulations. As needed, we can easily and quickly develop new stability-indicating assays that are closely tailored to protein characteristics and attributes. Furthermore, we can support stability studies of formulated products not only under accelerated conditions but also for long-term storage conditions, while adhering to cGMP requirements.

Figure 1: Charles River Formulation Paradigm

Diagram of Charles River formulation paradigm

The various formulation steps are summarized in the above diagram. For those products deemed unstable in liquid form, based on results from iterations 2 and 3, a lyophilization cycle is developed. We have experience utilizing most stabilizing excipients along with appropriate bulking and cryoprotectants. The optimization of the lyophilization cycle is also performed through a DOE approach, thus quickly homing in on the optimal lyophilization parameters. Once the cycle has been developed, then the top 2-3 lyo-formulation conditions are subjected to accelerated stability conditions from which the most stable formulation is selected.


We have expertise in the development of liquid and lyophilized formulations of proteins, peptides and other biologics products. Our formulation experience includes:

  • Various routes of administration (e.g., IV, IM, depot, ocular), several of which require high-concentration formulations
  • Typically insoluble molecules
  • Complex proteins
  • Multi-peptide formulated therapeutics


We can assist with the full formulation development cycle, as described above, or parts of the formulation cycle, as needed. Available formulation cycle packages include:

  • Pre-formulation
  • Formulation (liquid or lyophilized)
  • Forced degradation
  • Development of stability indicating analytical methods
  • Accelerated stability
  • Real-time stability
  • Various combinations of the above