Innovation and Technologies

Early detection of rheumatoid arthritis using biomarkers

Biomarkers are objective measures or indicators which are used to evaluate disease versus normal biological processes or responses to a drug or treatment. In the pharmaceutical R&D process, many different biomarker types are utilised for various purposes.

Biomarker types and applications span the broad spectrum of healthcare:

• Biomarkers for risk assessment permit the risk of an individual developing a particular disease to be estimated
• Biomarkers for earlier and more specific indication of  a compound’s toxicity
• Biomarkers for prognosis provide information about the likely course of a disease
• Biomarkers for patient stratification according to likely drug response allow physicians to identify the best treatment choice for a person
• Biomarkers for therapy monitoring provide information at an early stage as to whether treatment is working or if the disease is coming back

Examples:

• Blood pressure as a marker for hypertension.
• Herceptin, for example, was developed as effective treatment for breast cancer patients where the marker indicates if the tumour is HER2 positive, i.e., has a specific genetic trait.
• For HIV patients, monitoring the viral load, i.e. the number of viruses in the blood, is an effective biomarker. It is accepted by health authorities as a significant measurement in clinical trials for novel drugs such as Fuzeon which fights HIV before entering healthy cells in the first place. The combination of effective drug and biomarker is especially important for patients with limited therapeutic options.

Markers can be discovered, developed and validated through a variety of exciting new technologies ranging from genomics and proteomics to imaging tools. They have been widely installed and used across all divisions and functions within Roche.

It is the strategy of Roche to systematically pursue Personalised Healthcare (PHC) approaches for which biomarkers are essential. The most commonly cited example of PHC is the above mentioned Herceptin and its companion diagnostic tool, the Biomarker measuring HER2.

Neuraminidase and Tamiflu

In modern drug discovery, a programme usually starts with the selection of a biological “target” – usually a protein – that is believed to be associated with the disease state.  For targets where a small molecule therapeutic is preferred, medicinal chemists at Roche frequently use a technology called structure-based drug design (SBDD).  

This technology uses the three-dimensional structure of the target protein to design and optimise small organic molecules that bind to and affect the function of the target protein in the desired way. The availability of the 3D structure of the protein greatly reduces the empirical nature of drug design by allowing medicinal chemists to more rationally optimise small molecule drugs.  In essence, they are literally able to “see” where the best opportunities are to increase potency or modify other properties to make the drug more effective.

Roche was a pioneer in the area of structure-based design and has continually invested to maintain a technological advantage in this area.  A critical first step in SBDD is obtaining the crystal structure of the protein.  Through automation, miniaturization and parallel processing of all the steps required to create protein crystals, Roche is able to provide the protein crystal structure to medicinal chemists at a very early stage of the process for most programs.  Medicinal chemists and computational chemists then apply a number of tools to predict which changes in the initial lead molecules will give the desired improvements. These tools – many of which have been developed at Roche – use both databases of experimental data and theoretical methods to more effectively design the drug with the optimal properties.    

Computational methods have become an integral component of small molecule drug discovery research at Roche. Research proceeds in many iterative cycles of creating and synthesising new molecules and testing them in relevant biological assays, with the aim to optimise multiple properties in parallel. The amount of data created in these cycles is rapidly increasing and calls for advanced data mining methods to create improved hypotheses for the next generation of molecules.

A large toolbox of in silico methods exists for this purpose, ranging from methods correlating chemical structures with their properties and biological effects to fully automated virtual screening methods that help researchers to select promising candidates out of millions of (real or virtual) molecular structures. In some areas, computational screens are already replacing experimental measurement.

Modern scientific assessment of drug safety is increasingly using cell-based assays. Recent development in automation and miniaturization allow high throughput safety testing with minimal compound requirements already early in the R&D process. Roche’s efforts to guide the medicinal chemist in his design of new drugs that have favourable efficacy and safety profiles are driven by the need to increase the success rate of new drug candidates by using highly predictive technologies.

Cell based assays to assess drug behavior in the body (pharmacokinetics, drug metabolism), genotoxic liabilities, developmental toxicity (teratogenicity), cardiac toxicities, potential drug-drug interactions and other distinct toxicological mechanisms reflect Roche’s sustained commitment to reduce animal experimentation whenever possible while securing the safety of new drugs for the patients. Therefore an important aspect of the work is the constant exploration of new emerging technologies (e.g., high-content screening) and new cell-based approaches such as multiple cell type or stem cell derived models.

Molecular model of Therapeutic Protein

Therapeutic Proteins (TP) have increased dramatically in number and frequency of use since the introduction of the first recombinant protein — human insulin — 25 years ago and Roche's Roferon-A in 1986. These drugs usually display excellent affinity and selectivity for the disease target. In conjunction with favourable molecule properties like stability, long biological half-life, negligible susceptibility to unwanted metabolic degradation and low off-target adverse side effects TP offer excellent opportunities for Roche's commitment to innovative targeted drug therapies.

The Roche Group has generated a rich biological discovery, development and market (e.g. Rituxan, Herceptin, Avastin, NeoRecormon, Pegasys) pipeline based on cutting edge protein-engineering technologies as well as world-class manufacturing processes improving production, formulation and quality testing of protein drugs. The most recent example of this success story is ACTEMRA, the first humanised Interleukin-6 receptor-inhibiting monoclonal antibody representing a novel mode of action for treatment of Rheumatoid Arthritis.

Roche scientists are actively working on the next wave of therapeutic proteins focussing on rational design and engineering the drug with desired properties (like glyco-engineering of monoclonal antibodies to enhance antibody-dependent cellular cytotoxicity, combining two functionalities in one drug or optimising targeted delivery).

One mechanism by which therapeutic monoclonal antibodies can perform target cell killing is antibody-dependent cellular cytotoxicity (ADCC). The efficiency of ADCC is strictly dependent on the recruitment of immune effector cells, like NK cells, via FcμIIIa receptor binding. One possibility to enhance FcμIIIa binding is the engineering of N-linked oligosaccharide structures attached to the Fc region of monoclonal antibodies. This glycoengineering approach (GlycoMAb) generates novel antibody glycovariants with significantly enhanced FcμIIIa binding and improved tumour target cell killing.

Currently new glycoengineered monoclonal antibodies for treatment of different tumours are in development at Roche. One, a novel anti CD20 antibody directed against an epitope on malignant and normal human B-cells, already demonstrated superior efficacy in different preclinical non-Hodgkin lymphoma (NHL) models. Roche also has generated a recombinant, glycoengineered monoclonal antibody that is directed against EGFR, an antigen expressed on many solid tumours such as lung, colon and head and neck cancer and it could be demonstrated clearly that glycoengineering also significantly enhanced ADCC activity of this antibody.

Discovery Technologies provide the critical platforms and technologies for the identification of active small molecules and their further optimization in the drug discovery process.  Using state of the art robotics, molecular and cell biology, fermentation techniques, liquid handling devices, ultra-sensitive detectors, and sophisticated data processing software, we can manage and dispense over 1 million compounds on demand, generate biochemical and cellular assays and conduct High throughput screens where we can carry out millions of biochemical or pharmacological tests to rapidly identify compounds which modulate a particular biological pathway.  X-Ray Crystallography and Protein NMR provide critical 3-dimensional structural data of these compounds bound to the target proteins allowing for triage of the leads and guidance for further optimisation of drug like properties.

Using Ambit Biosciences screening technology, KINOMEscan™, a high-throughput active-site dependent competition binding assay, Roche is able to identify the effects of drug candidates on kinases. This class of enzymes regulates cellular functions such as their proliferation, immune response or death and has been linked to numerous diseases including cancer, arthritis, and respiratory diseases. The challenge in kinase research is to create inhibitors that selectively alter the activity of specific kinases for therapeutic benefit while not indiscriminately inhibiting the 518 kinases in the human genome. At Roche, the fast screening of drug candidates versus more than 400 kinases is already possible. The resulting selectivity profiles guide the design of drug candidates to optimise for both efficacy and safety. In addition, with a multidisciplinary approach, Roche expects to utilise its kinase profiling data to reveal unforeseen benefits for our drug candidates across multiple diseases.

Here are three examples of Roche’s innovative research into formulation to ensure that novel compounds / medicines achieve their therapeutic effect:

Making compounds (bio)available

A common challenge in developing drugs is achieving the required systemic exposure, particularly for poorly soluble compounds. Roche scientists have developed proprietary formulation technology platforms for converting insoluble drugs to stable, water-soluble amorphous complexes based on spray-drying, solvent precipitation, fluid bed layering and hot melt extrusion techniques. These technologies have enabled systemic exposure sufficient for clinical development.

Solvent evaporation, or spray-drying, and anti-solvent precipitation techniques are based on dissolving the drug and polymer in a suitable solvent, and either flash-evaporating or precipitating the drug-polymer complex as an amorphous solid. The principle of hot melt extrusion is to form a co-melt of the drug and polymer (carrier), which is then rapidly cooled to yield an amorphous ‘glass.’

Since one technology doesn’t fit all, Roche formulation scientists have developed further expertise to deliver the poorly soluble compounds using nanoparticles or lipid formulations.  There is also a continuous effort to screen external technologies for optimal delivery of poorly soluble drugs.

Delivery of RNAi Therapeutics

Ribonucleic acid interference (RNAi) is a major scientific breakthrough and offers limitless opportunities for therapeutics.  While the science of RNAi is fast developing, Roche scientists are looking into the major challenges to unravel the puzzle for successful intracellular delivery of siRNA an absolute requirement for developing effective siRNA based treatments. The current major challenges are attributed to their short in-vivo half life, rapid renal elimination from the body, achieving sufficient concentration of these molecules in the tissue of interest in the body and then traversing the natural cellular barriers to gain entry in the cell to activate the RNAi mechanism.

Roche researchers are working on a multi-faceted strategy to address these challenges. This strategy encompasses the target-driven optimisation of delivery systems by introducing unique chemical modifications to the siRNA molecule itself and also developing novel formulation vehicles to improve biodistribution and in-vivo sustenance. These vehicles range from liposomes to polymer-based nanoparticles that utilise natural and synthetic polymers and complexing agents. The siRNA drug delivery teams are tapping into the vast innovation networks within Roche and exploring external company and academic collaborations, such as the recently announced partnership with Tekmira and a fruitful cooperation with Dalian University in China.   

Halozyme Enhanze™ Drug Delivery Technology

With a large portfolio of biologics on the market and in development finding ways to deliver these compounds safely and conveniently is a high priority at Roche. Applying s.c. administration instead of i.v. dosing offers a major safety and convenience advantage to doctors and patients allowing for example self-administration at home instead of receiving an infusion at the hospital.

In December 2006 Roche and Halozyme Therapeutics, Inc. have entered into an agreement to apply Halozyme’s Enhanze™ Technology to Roche’s biological therapeutic compounds. This Drug Delivery Technology is based on the biological activity of a naturally occurring human enzyme (PH20 hyaluronidase),  which is known to play a key role in the regeneration of the subcutaneous tissue by temporarily breaking down hyaluronic acid, the space-filling "gel"-like substance that is a major component of it. When injected subcutaneously, hyaluronidase acts as a spreading agent that accelerates the delivery of co-injected drugs and increases their systemic bioavailability. The enzyme is degraded within minutes making this process fully reversible. The use of this Delivery Technology further allows subcutaneous (sc) administration of larger volumes (e.g. to 5 to 20 mL) without causing discomfort for the patients. To exploit the full benefit of this technology Roche scientist are also exploring suitable injection devices for easy and safe patient use.  

A large body of clinical experience supports the benefits and safety of using PH20 hyaluronidase as an adjuvant in drug product formulations. The use of recombinant human hyaluronidase is approved in the US.

To support excellence in decision making within Roche Research we invest significantly in information and informatics. Through the use of bioinformatics, cheminformatics, statistics, information science and knowledge engineering Roche enables innovation in drug discovery and development.  Ensuring that we derive maximum value from the latest genomic data, for example, requires a sophisticated bioinformatics platform and skilled scientists.  Using the large volumes of publicly available information, plus Roche internal information, Roche is able to construct genome and gene expression maps and biological pathway models from different organs, populations of patients, disease stages, and so on. Computational models enable us to compare these and generate hypotheses as to the causes of disease and where Roche can target its research efforts to develop drugs that are highly efficacious and safe for the patients who will receive them.