Understanding how antibody therapies work, why they differ from chemotherapy, and what to expect during treatment
Antibody-based therapies have transformed the treatment of many cancers and are among the most precise treatments available in modern oncology.
Unlike traditional chemotherapy, which affects rapidly dividing cells throughout the body, antibody therapies are designed to recognise specific targets found on cancer cells or within the tumour environment.
These treatments can improve outcomes while often reducing some of the broader side effects associated with conventional chemotherapy. However, they can still produce important side effects and require careful monitoring throughout treatment.
Understanding how antibody therapies work can help patients feel more informed and confident throughout their treatment journey.
Understanding Antibody-Based Therapies
What Are Antibody-Based Therapies?
Antibodies are proteins naturally produced by the immune system.
Their normal role is to recognise and attach to specific targets, such as viruses, bacteria or abnormal cells.
Scientists have learned how to create specialised antibodies that recognise particular features found on cancer cells.
These laboratory-produced antibodies are known as monoclonal antibodies.
Once attached to their target, they can:
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Block growth signals used by cancer cells
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Mark cancer cells for destruction by the immune system
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Interfere with the tumour's blood supply
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Deliver drugs directly to cancer cells
Because they are designed to target specific biological features, antibody therapies are often considered a form of precision medicine.
The "Smart Missile" Concept
Many patients find it helpful to think of antibody therapies as guided missiles.
Traditional chemotherapy circulates throughout the body and affects many rapidly dividing cells.
Antibody therapies, by contrast, are designed to identify a specific target and attach directly to it.
Once attached, they can:
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Block important growth signals
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Recruit the immune system
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Deliver a treatment payload directly to the cancer cell
This targeted approach is one reason antibody therapies have become such an important part of modern cancer care.
How Do Antibody Therapies Work?
Different antibody therapies work in different ways.
Blocking Growth Signals
Some cancers depend on specific receptors to receive instructions to grow and divide.
Certain antibodies attach to these receptors and block those signals.
Examples include:
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Trastuzumab (Herceptin)
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Pertuzumab (Perjeta)
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Cetuximab (Erbitux)
By blocking these pathways, cancer growth may slow or stop.
Helping the Immune System Recognise Cancer
Some antibodies act like markers.
Once attached to a cancer cell, they make it easier for the immune system to identify and destroy that cell.
In effect, they place a visible "target" on the cancer for immune cells to attack.
Blocking the Blood Supply
Tumours require oxygen and nutrients to grow.
Certain antibodies work by interfering with the development of new blood vessels.
Examples include:
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Bevacizumab (Avastin)
By reducing the tumour's blood supply, growth may be slowed.
Delivering Treatment Directly to Cancer Cells
Some of the newest antibody therapies combine an antibody with a powerful anti-cancer drug.
These treatments are known as Antibody-Drug Conjugates (ADCs)
The antibody acts as a guidance system, carrying the drug directly to the cancer cell.
Once attached, the drug is released where it is needed most.
Examples include:
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Trastuzumab emtansine (T-DM1)
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Trastuzumab deruxtecan (Enhertu)
This approach aims to maximise effectiveness while reducing exposure to healthy tissues.
Which Cancers Can Be Treated With Antibody Therapies?
Antibody therapies are now used in many cancers, including:
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Breast cancer
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Colorectal cancer
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Lung cancer
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Gastric cancer
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Ovarian cancer
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Lymphoma
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Head and neck cancers
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Several blood cancers
Whether an antibody therapy is appropriate depends on the specific characteristics of the tumour and the presence of particular molecular targets.
How Do Antibody Therapies Differ From Chemotherapy?
Chemotherapy Antibody Therapy
Targets rapidly dividing cells Targets specific proteins or receptors
Acts broadly throughout the body Acts on carefully selected targets
Often affects many healthy tissues Generally more selective
Hair loss is common with many regimens Hair loss is less common with many antibody therapies
Side effects often result from effects on rapidly dividing cells Side effects often relate to the biological target being affected
Usually given in cycles May be given regularly over many months or years
Although antibody therapies are often more precise, they can still cause significant side effects and require close monitoring.
Why Do Side Effects Occur?
Even though antibody therapies are designed to be selective, the targets they recognise may also be present in healthy tissues.
In addition, activating the immune system or interfering with normal biological pathways can sometimes affect healthy organs.
The pattern of side effects varies considerably depending on:
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The specific antibody being used
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The cancer being treated
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Previous treatments
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Individual biological factors
Common Side Effects of Antibody Therapies
Not everyone experiences side effects, and many people tolerate treatment well.
However, some common challenges include:
Fatigue
Fatigue remains one of the most frequently reported side effects.
It may affect energy levels, concentration and physical function.
Infusion Reactions
Because many antibody therapies are given intravenously, some patients experience reactions during or shortly after treatment.
Symptoms may include:
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Fever
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Chills
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Flushing
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Headache
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Shortness of breath
Healthcare teams monitor patients closely during infusions.
Skin Changes
Some antibody therapies can affect the skin.
Symptoms may include:
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Rash
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Dry skin
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Sensitivity
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Itching
Digestive Symptoms
Some patients experience:
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Diarrhoea
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Nausea
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Appetite changes
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Abdominal discomfort
Mouth Problems
Certain treatments may contribute to:
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Mouth soreness
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Oral discomfort
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Changes in taste
Cardiovascular Effects
Some therapies, particularly HER2-targeted treatments, may require monitoring of heart function during treatment.
This does not affect everyone, but regular assessment is often part of routine care.
Reduced Physical Function
Fatigue, treatment schedules and cumulative side effects can affect confidence, activity levels and physical conditioning.
Emotional Wellbeing
Long-term treatment can affect emotional resilience, confidence and quality of life.
When Should You Contact Your Oncology Team?
Always follow the advice provided by your oncology team.
Contact your team promptly if you experience:
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A temperature of 38°C or above
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Shortness of breath
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Chest pain
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Significant skin reactions
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Persistent diarrhoea
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Severe fatigue
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Rapidly worsening symptoms
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Any symptom specifically highlighted by your treatment team
Early reporting often helps prevent more serious complications.
Why Early Support Matters
Different antibody therapies are associated with different patterns of side effects.
Understanding the treatment pathway allows supportive care to be introduced proactively rather than waiting until symptoms significantly affect quality of life.
Depending on the treatment being received, early support may focus on:
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Fatigue management
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Maintaining physical function
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Supporting recovery between treatments
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Managing skin and soft tissue changes
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Sleep support
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Emotional resilience
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Education and self-management strategies
The goal is to help individuals maintain function, independence and quality of life throughout treatment.
How Rowan Health Supports Patients Receiving Antibody-Based Therapies
At Rowan Health, support is organised around personalised treatment-pathway support protocols rather than standardised treatment packages.
Different antibody therapies may be associated with different patterns of side effects and recovery challenges. Our approach aims to anticipate these challenges where possible and provide proactive support throughout treatment and recovery. This aligns with the wider Rowan Health model of tailoring support to the specific treatment pathway and likely areas of vulnerability.
Step 1 – Understanding the Treatment Pathway
We begin by understanding:
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The cancer diagnosis
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The antibody therapy being received
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Previous treatments
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Current symptoms
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Recovery goals
Step 2 – Identifying Areas of Vulnerability
We assess factors most likely to affect quality of life, including:
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Fatigue
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Skin and soft tissue changes
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Digestive symptoms
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Sleep disruption
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Reduced physical function
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Emotional wellbeing
Step 3 – Building a Personalised Support Protocol
Depending on the individual's needs, the protocol may combine:
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Symptom management
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Rehabilitation
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Recovery support
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Education and self-management strategies
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Selected therapeutic interventions
Step 4 – Monitoring, Adapting and Supporting Recovery
Treatment and recovery are dynamic processes.
Protocols are reviewed and adapted as symptoms, treatment schedules and recovery priorities evolve.
Our Goal
Our objective is not simply to respond to symptoms as they arise.
It is to provide proactive, coordinated support that helps individuals:
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Maintain function and independence
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Improve quality of life
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Strengthen resilience
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Reduce the burden associated with treatment
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Support recovery and rehabilitation
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Navigate survivorship with greater confidence
Areas We Commonly Support During Antibody-Based Therapy
The type and severity of side effects varies according to the specific antibody therapy being used, the cancer being treated and the individual's overall health.
Not everyone experiences the same challenges. However, some of the most common areas where patients seek supportive care include:
Fatigue and Reduced Energy
Fatigue remains one of the most frequently reported challenges during antibody-based therapy.
Unlike ordinary tiredness, treatment-related fatigue may persist despite rest and can affect physical activity, concentration, motivation and overall quality of life.
For some individuals, fatigue develops gradually over the course of treatment and may fluctuate from one treatment cycle to another.
Skin and Soft Tissue Changes
Certain antibody therapies can affect the skin and surrounding tissues.
Patients may experience:
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Dry skin
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Rash
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Itching
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Increased skin sensitivity
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Delayed skin healing
Although these symptoms are often manageable, they can affect comfort, confidence and daily activities.
Digestive Difficulties
Some patients experience treatment-related digestive symptoms, including:
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Nausea
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Reduced appetite
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Diarrhoea
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Altered bowel habits
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Abdominal discomfort
The impact of these symptoms varies considerably between individuals and may influence nutrition, hydration and energy levels.
Reduced Physical Function
Cancer treatment itself, combined with fatigue and reduced activity levels, can contribute to physical deconditioning.
Some patients notice:
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Reduced stamina
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Loss of strength
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Reduced confidence in physical activity
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Difficulty returning to previous levels of function
Maintaining physical function throughout treatment is often an important component of recovery and long-term wellbeing.
Sleep Difficulties
Sleep may be affected by:
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Treatment schedules
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Physical symptoms
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Fatigue
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Anxiety and uncertainty
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Changes in routine
Poor sleep can contribute to reduced energy, impaired concentration and slower recovery.
Cognitive Difficulties
Although less commonly discussed than during chemotherapy, some individuals report:
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Difficulty concentrating
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Mental fatigue
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Reduced mental clarity
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Memory lapses
These changes are often influenced by multiple factors, including cancer itself, fatigue, sleep disruption and the cumulative burden of treatment.
Emotional Wellbeing and Adjustment
Living with cancer and ongoing treatment can affect emotional wellbeing in many ways.
Individuals may experience:
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Anxiety
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Uncertainty
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Reduced confidence
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Frustration
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Difficulties adapting to treatment and recovery
These challenges can occur even when treatment is progressing successfully.
Long-Term Treatment Adaptation
Unlike some cancer treatments that are delivered over a relatively short period, certain antibody therapies may continue for many months or even years.
Patients may therefore require support in adapting to:
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Long-term treatment schedules
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Ongoing monitoring
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Maintaining work and family responsibilities
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Balancing treatment with everyday life
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Preserving quality of life during extended treatment
Particular Considerations for Antibody-Drug Conjugates (ADCs)
Some modern antibody therapies are combined with chemotherapy drugs in the form of Antibody-Drug Conjugates (ADCs).
Because these treatments deliver a chemotherapy payload directly to cancer cells, some patients may also experience challenges more commonly associated with chemotherapy, including:
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Fatigue
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Peripheral neuropathy
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Digestive symptoms
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Nail and skin changes
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Cognitive difficulties ("brain fog")
The pattern of side effects depends on the specific ADC being used and the individual's response to treatment.
Understanding Treatment, Recovery and Support
Explore our detailed guides:
Cancer Treatments
➡ Understanding Cancer & Cancer Treatments
➡ Understanding Hormonal Therapy
➡ Understanding CAR-T Cell Therapy
Treatment challenges
➡ Why Side Effects Happen
➡ Cancer-Related Fatigue
➡ Chemo Brain
➡ Peripheral Neuropathy
➡ Xerostomia (Dry Mouth)
➡ Mucositis
➡ Skin and Nail Changes During Cancer Treatment
➡ Sleep Difficulties
Recovery & Support
➡ Cancer Support & Survivorship
➡ Carers' Wellbeing
➡ Recovery After Cancer Treatment
Need Support?
Every anti-body based therapy journey is different.
If you would like to discuss supportive care during treatment or recovery, Rowan Health offers personalised consultations designed around your diagnosis, treatment pathway, symptoms and recovery goals.