The development of protective herpes simplex virus (HSV) vaccines has been an ongoing challenge for decades. Many vaccine candidates are under development, including DNA, modified mRNA, protein subunit, killed virus, and attenuated live virus vaccines.
The herpes simplex virus exists as 2 biologically distinct serotypes, HSV-1 and HSV-2, which differ mainly by their transmission mode, says the U.S. CDC.
Herpes Vaccine Candidates
Clinical researchers have been developing herpes vaccines in clinical trials to test therapeutic (intended to reduce viral shedding in people who are already infected with HSV) and preventive (designed to prevent infection) vaccine candidates.
HSV529 (HSV15) is a vaccine candidate classified as a replication-defective virus, meaning the virus possesses all the wild-type HSV virus components except two proteins UL5 and UL29, involved in viral DNA replication. This phase 1/2 study was last updated on November 27, 2020, by Sanofi Pasteur.
EXD-12 is a vaccine candidate currently in preclinical testing for safety and efficacy as both a prophylactic and therapeutic vaccine for both Herpes Simplex Virus-1, HSV-1, and Herpes Simplex Virus-2, HSV-2.
Delta gD-2 (∆gD-2) is a vaccine candidate based on an HSV-2 virus genetically deleted for glycoprotein D (gD-2).
NanoVax is an adjuvant platform used to develop a vaccine candidate to protect against the two viruses that can cause genital herpes.
GSK’s Simplirix HerpeVac was in a double-blind, randomized, controlled phase 3 clinical study to assess the prophylactic efficacy and safety of gD-Alum/MPL vaccine in the prevention of genital herpes disease in young women who are herpes simplex virus (HSV)-1 and -2 seronegative. Last updated during August 2018.
GSK's HSV vaccine (GSK4108771A) launched the first-time-in-human phase 1 clinical study to assess the reactogenicity, safety, and immunogenicity of four different dose levels of an experimental herpes simplex virus type 2 (HSV-2) vaccine when administered intramuscularly on a 0, 2-month schedule to healthy participants aged 18-40 years. The Estimated Primary Completion Date is August 9, 2022.
Herpes Vaccines - Pre-Clinical Development
RVx-201 HSV-2 vaccine candidate is designed to have a specific degree of attenuation through specifically designed mutations in the ICP0 protein.
The VC2 vaccine candidate is a live-attenuated, engineered version of HSV-1. The VC2 vaccine targets facial, ocular, and genital herpes caused by HSV-1 and protects against genital herpes caused by HSV-2.
Herpes Vaccine Development News
April 5, 2021 - Rational Vaccines announced a license agreement for the work of Louisiana State University virologist Dr. Konstantin 'Gus' Kousoulas from LSU's School of Veterinary Medicine in the Division of Biotechnology & Molecular Medicine that furthers Rational's core mission of eliminating herpes virus. The vaccine technology, known as VC2, demonstrated great promise in treating Herpes Simplex Virus 1 and 2 and facial and ocular herpes in several animal model studies. Unlike vaccines that use individual viral proteins to vaccinate patients, VC2 is a live-attenuated, engineered version of HSV-1. Because VC2 prevents HSV from entering the body's neurons, Kousoulas believes that it is a safe and effective option for the prevention and potential therapeutic treatment of herpes. VC2 also replicates well in many validated vaccine production cell lines, making it cost-effective to produce and therefore more accessible to patients.
April 5, 2021 - Austin, Texas-based Maxwell Biosciences announced that the peer-reviewed, open-access journal Pharmaceuticals published scientific research findings co-authored by Gill Diamond, Ph.D. (University of Louisville), and eleven other collaborating academic researchers. Titled Potent Antiviral Activity against HSV-1 and SARS-CoV-2 by Antimicrobial Peptoids, the research findings demonstrate that several peptoids exhibit potent in vitro antiviral activity against both Herpes Simplex Virus-1 (HSV-1) and SARS-CoV-2. As outlined in the paper’s abstract, viral infections, such as those caused by HSV-1 and SARS-CoV-2, affect millions of people each year. However, few drugs treat viral infections effectively, and no vaccine to prevent HSV-1 infections exists.
March 30, 2021 - Two novel vaccine candidates for the prevention and treatment of genital herpes have shown to be safe in pre-clinical animal studies, according to a study published in the journal Vaccines. "These results are encouraging and validate the need for continued development and testing of these live-attenuated vaccine candidates, which are historically underdeveloped vaccine types for the treatment or prevention of genital herpes," said Jonathan Joyce, the lead author of the study and Ph.D. candidate in Dr. Andrea Bertke's group at the Department of Population Health Sciences, Virginia Tech.
March 19, 2021 - A study of Rational Vaccines’ herpes simplex virus candidate published in the Journal of Virology demonstrates that the vaccine candidate, RVX10, offered robust protection against ocular herpes simplex virus 1 (HSV-1) infection in vaccinated mice. The major finding of the study, “Herpes Simplex Virus 1 (HSV-1) 0ΔNLS Live-Attenuated Vaccine Protects against Ocular HSV-1 Infection in the Absence of Neutralizing Antibody in HSV-1 gB T Cell Receptor-Specific Transgenic Mice,” found that the company’s RVX101 vaccine candidate used to immunize a unique mouse line (does not generate much of a neutralizing antibody response to the virus) was shown to provide highly protective immunity and prevent herpes-associated neovascularization. This robust efficacy was correlated with CD8+ T cells since depleting these cells after vaccination, but before the challenge with HSV-1 eliminated any efficacy realized by the vaccine. Ocular HSV can cause disease in any layer of the eye and is mainly spread by direct contact. A variety of eye diseases are associated with ocular HSV infection, including conjunctivitis, iridocyclitis, acute retinal necrosis, and keratitis.
March 18, 2021 - GlaxoSmithKline launched a Phase I, Single-blind, Randomised, Placebo-controlled, Dose Escalation Study to Evaluate the Reactogenicity, Safety and Immune Response of gE/gI SAM (LNP) Vaccine in (60) Healthy Participants Aged 18-40 Years.
March 13, 2021 - The journal Vaccines published a study: Assessment of Two Novel Live-Attenuated Vaccine Candidates for Herpes Simplex Virus 2 (HSV-2) in Guinea Pigs. Two experimental, novel live-attenuated HSV-2 vaccine candidates (RVx201 and RVx202) have been tested preclinically for safety. This study's findings suggest that these novel vaccine candidates are safe in guinea pigs and should be tested for efficacy as preventative and/or therapeutic anti-HSV-2 vaccines.
March 5, 2021 - The BMJ published an opinion article, 'Understanding the spectrum of vaccine efficacy measures.' Efficacy against severe disease is perhaps of greatest clinical relevance. Yet vaccine efficacy for preventing infection is harder to measure reliably. Preventing infection clearly also prevents transmission and symptoms, yet vaccines can offer clinical benefit by priming the immune system to prevent symptoms even despite infection. Thus, vaccine efficacy against infection cannot be higher than efficacy against disease. For example, from another disease, in 2012, the efficacy of a herpes simplex vaccine against herpes simplex virus 1 genital disease was 58% (95% CI 12 to 80%). Still, efficacy against herpes simplex virus 1 infection was 35% (95% CI 13 to 52%).
February 26, 2021 - Massachusetts-based Rational Vaccines announced virologist Konstantin "Gus" Kousoulas joined the company as vice president of Scientific Affairs, where he will further its core mission eradicating the world of the herpes simplex virus. Kousoulas is a professor of virology and biotechnology in the Louisiana State University Department of Pathobiological Sciences and the Division of Biotechnology and Molecular Medicine.
February 14, 2021 - RESEARCH ARTICLE: Herpesvirus infections, antiviral treatment, and the risk of dementia—a registry‐based cohort study in Sweden. Antiviral treatment was associated with a reduced long‐term risk of dementia among individuals with overt signs of herpes infection. This is consistent with earlier findings indicating that herpes viruses are involved in the pathogenesis of AD.
February 12, 2021 - Study: Neuronal hyperexcitability is a DLK-dependent trigger of herpes simplex virus reactivation that IL-1 can induce. 'HSV-1 co-opts an innate immune pathway resulting from IL-1 stimulation of neurons to induce reactivation.'
February 12, 2021 - The journal Nature published a study: Transient editing catches the eye. A one-shot transient approach for therapeutic gene editing is, therefore, an advantageous proposition on many fronts.
February 10, 2021 - Commercial firms in the herpes marker testing market are making strides for diagnostic tests for HSV1- and HSV- 2. In 2014, Simplexa HSV 1 and HSV 2 direct molecular tests by Quest Diagnostics were the first to receive U.S. FDA’s approval. The Simplexa test is the first one approved by the U.S. FDA that enables qualitative differentiation and detection of HSV-1 and HSV- 2 in cerebrospinal fluid. Other top firms in the herpes marker testing market are Trinity Biotech, Biohelix, Focus Diagnostics, DiaSorin, Roche, Thermo Fisher Scientific, and Enzo Life Sciences.
February 9, 2021 - Quercus Molecular Design (QMD) develops broad-spectrum antiviral drugs with indications ranging from herpes viruses to SARS-CoV2. Sandra Weller, QMD’s chief biology officer and Board of Trustees Distinguished Professor of molecular biology and biophysics in UConn’s School of Medicine, studied the mechanism of replicating human herpes viruses for more than 40 years. Weller paired her in-depth understanding of the molecular mechanisms of viral replication with Dennis Wright's expertise, a professor of medicinal chemistry in the UConn School of Pharmacy and QMD’s chief chemistry officer. Wright’s lab develops chemical compounds that target and block specific proteins in pathogens from performing their function, thus preventing the pathogen from growing.
February 9, 2021 - According to Google Trends, searches for the term “covid shingles” hit peak popularity on the search engine over the past week. "There is no scientific evidence of this [association]," says Aaron Glatt, MD, chief of infectious diseases at Mount Sinai South Nassau in Oceanside, NY, and a spokesperson for the Infectious Diseases Society of America, reported WebMD.
February 3, 2021 - RESEARCH ARTICLE published by PLOS: Safety, acceptability, and pharmacokinetics of a monoclonal antibody-based vaginal multipurpose prevention film (MB66): A Phase I randomized trial. Single and repeated intravaginal applications of MB66 film were safe, well-tolerated, and acceptable. Concentrations and ex vivo bioactivity of both mAbs in vaginal secretions were significantly elevated and could protect for at least 24 hours postdose. However, further research is needed to evaluate the efficacy of MB66 film in women at risk for HIV and HSV infection. Additional antibodies could be added to this platform to protect against other sexually transmitted infections and contraception.
February 1, 2021 - Virios Therapeutics, Inc. (Nasdaq: VIRI), a biotechnology company focused on advancing novel antiviral therapies to treat diseases associated with a viral triggered abnormal immune response, announced today that it is entering a collaboration with Dr. Michael Camilleri of the Mayo Clinic to explore the role of antiviral therapy in managing Irritable Bowel Syndrome (IBS). The overactive immune response related to activation of tissue-resident Herpes Simplex Virus-1 (“HSV-1”) has been postulated to be a potential root cause of chronic illnesses such as FM, irritable bowel disease, chronic fatigue syndrome, and functional somatic syndrome, all of which are characterized by a waxing and waning manifestation of the disease.
January 13, 2021 - Study Update of the Safety of a Particular Herpes Vaccine in Adults With or Without Herpes Infection. Phase I Study of the Safety of replication-defective Herpes Simplex Virus-2 Vaccine, HSV529, in Adults Aged 18 to 40 Years With or Without HSV Infection. Study Start Date: September 26, 2013.
January 11, 2021 - A press release by Rational Vaccines herpes focused on the study published in the Journal of Virology on November 23, 2020, demonstrates that the vaccine candidate, RVX10, offered robust protection against ocular herpes simplex virus 1 (HSV-1) infection in vaccinated mice found that the company's RVX101 vaccine candidate used to immunize a unique mouse line (does not generate much of a neutralizing antibody response to the virus) was shown to provide highly protective immunity and prevent herpes-associated neovascularization. This robust efficacy was correlated with CD8+ T cells since depleting these cells after vaccination but before challenge with HSV-1 eliminated any usefulness realized by the vaccine.
November 30, 2020 - In this systematic review of Medline, EMBASE, and PubMed studies, there were 16 articles deemed relevant comprising both animal and human studies (301 patients) regarding the use of the Bacillus Calmette‐Guérin (BCG) vaccine’s off‐target effects that might impact the recurrence of HSV infections. In non-randomized human studies (that failed to control for a placebo effect), BCG vaccination appeared beneficial in 78 percent of adults with recurrent herpes genitalis or labialis, with 37 percent being recurrence‐free for an extended period, 41 percent experiencing less frequent or severe episodes, and only 22 percent reported no change. This clinical benefit is consistent with the findings of immunological sub‐studies. In the two studies restricted to recurrent herpes labialis, 94 percent appeared to benefit from BCG.
November 23, 2020 - Study published by American Society for Microbiology: Collectively, the study suggests CD8+ T cells significantly contribute to the host adaptive immune response to HSV-1 challenge following vaccination with an attenuated virus, but multiple factors are involved in cornea pathology in response to ocular virus challenge. The current study shows that in the near absence of anti-HSV-1 antibodies, vaccinated mice are protected from subsequent challenges with wild-type HSV-1 as measured by survival. The efficacy is lost following depletion of CD8+ T cells. Whereas increased survival and reduction in virus replication were observed in vaccinated mice challenged with HSV-1, cornea pathology was mixed with a reduction in neovascularization but no opacity change.
November 9, 2020 - MedicalResearch.com Interview with Gary E. Pickard, Ph.D., Professor of Neuroscience, School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln.
November 6, 2020 - Study published by Nature: The R2 non-neuroinvasive HSV-1 vaccine affords protection from genital HSV-2 infections in a guinea pig model. The use of live-attenuated HSV vaccines that robustly replicate in mucosal tissues but are ablated for neuroinvasion offers a promising approach for HSV vaccines. The study found that vaccinating guinea pigs with the modified live virus significantly increased virus-combating antibodies. When challenged with a virulent strain of herpes simplex virus, the vaccinated animals displayed fewer genital lesions, less viral replication, and less the viral shedding that most readily spreads the infection to others.
November 3, 2020 - Protection against herpes simplex virus type 2 infection in a neonatal murine model using a trivalent nucleoside-modified mRNA in lipid nanoparticle vaccine. Neonatal herpes is a dreaded complication of genital herpes infection in pregnancy. We recently compared two vaccine platforms for preventing genital herpes in female mice and guinea pigs. We determined that HSV-2 glycoproteins C, D, and E expressed using nucleoside-modified mRNA in lipid nanoparticles provided better protection than the same antigens produced as baculovirus proteins and administered with CpG and alum.
September 25, 2020 - Study: Cell entry of enveloped viruses requires specialized viral proteins that mediate fusion with the host membrane by substantial structural rearrangements from a metastable pre- to a stable postfusion conformation. This metastability renders the herpes simplex virus 1 (HSV-1) fusion glycoprotein B (gB) highly unstable such that it readily converts into the postfusion form, thereby precluding structural elucidation of the pharmacologically relevant prefusion conformation.
September 24, 2020 - Study review: the BCG vaccine is a potential, safe, affordable, and readily available candidate intervention to decrease the high burden of disease associated with HSV infection and recurrences, but properly controlled randomized trials are required.
September 24, 2020 - Study: In summary, almost half of patients with mild‐to‐moderate COVID‐19 admitted in a field hospital during a 2‐week period showed mucocutaneous findings. The oral cavity was frequently involved and deserves specific examination under appropriate circumstances to avoid contagion risk. Redness and swelling of the hands and feet, fine palmoplantar desquamation, and reddish‐to‐brown macules can help us diagnose COVID‐19 infection and be routinely checked.
September 15, 2020 - Dr. Roach: HSV diagnosis doesn’t need to doom love life.
August 18, 2020 - A recent study evaluated HSV gene editing in a well-established mouse model, using adeno-associated virus (AAV)-delivered meganucleases as a potentially curative approach to treat latent HSV infection. Here we show that AAV-delivered meganucleases, but not CRISPR/Cas9, mediate highly efficient HSV gene editing, eliminating over 90% of latent virus from superior cervical ganglia. The levels of HSV elimination observed in these studies, if translated to humans, would likely significantly reduce HSV reactivation, shedding, and lesions.
August 14, 2020 - Research study: HVEM signaling promotes protective antibody-dependent cellular cytotoxicity vaccine responses to herpes simplex viruses.
July 27, 2020 - RESEARCH ARTICLE: An HSV-2 nucleoside-modified mRNA genital herpes vaccine containing glycoproteins gC, gD, and gE protects mice against HSV-1 genital lesions and latent infection.
July 27, 2020 - Vaccines against Genital Herpes: Where Are We? Because of the high burden of genital herpes, HSV vaccines have been developed, but none have been very successful. This review discusses the current status of genital herpes vaccine development.
July 27, 2020 - In a mice study, these researchers compared protection by the HSV-2 mRNA vaccine against genital HSV-1 and HSV-2 infection. Mice infected with either virus were totally protected from genital disease. Significantly, in two experiments, the mRNA vaccine prevented HSV invasion of the dorsal root ganglia, the site of virus latency, in 39/40 (97.5%) mice infected with either HSV-1 or HSV-2. They conclude that the HSV-2 trivalent mRNA vaccine provides potent protection against HSV-1 and HSV-2 genital infection and is a promising vaccine candidate for human trials.
July 24, 2020 - Over 65% of young people have their first sexual activity unexposed to herpes but risk catching it in adulthood, stated a new study. This research found fewer people are being exposed to HSV-1, also known as oral herpes, in their youth.
July 23, 2020 - Study: Tetrameric glycoprotein complex gH/gL/gQ1/gQ2 is a promising vaccine candidate for human herpesvirus 6B. HHV 6 is a group of various viruses belonging to the herpes virus family. HHV-6B causes a disease called exanthema subitum or roseola infantum in children and infants. It is one of the most common causes of emergency hospitalization in children up to 3 years of age. HHV6B tetramer or gH/GL/gQ1/gQ2 is a protein on the surface of the HHV6 virus that interacts with the human CD134 (a protein present on T cells) to gain entry into host cells. As viruses are intracellular parasites, they need a living cell to survive.
July 21, 2020 - The story of Rational Vaccines' pursuit of a therapeutic vaccine for genital herpes may go down as one of the strangest and most controversial chapters in the history of drug or vaccine development.
July 17, 2020 - This article sheds light on the molecular and structural interactions between HHV-6B tetramer and its host receptor, along with their neutralizing antibodies and their affinities, competition, and binding modes based on the HHV-6B tetramer structure are described. Our findings provide molecular and structural bases for a comprehensive understanding of these interactions and relationships.
July 16, 2020 - Herpes simplex virus type 1 in Europe: a systematic review, meta-analyses, and meta-regressions. The results showed that more than two-thirds (67.4%) of tEurope'spopulation tested positive for HSV-1, which is far lower than the historical level of universal infection in childhood in other parts of the world, such as Africa. Around 32.5% of children and 74.4% of adults were infected in Europe. The results also showed that half of the first-episode genital herpes cases in Europe were already due to HSV-1 instead of HSV-2 infection.
July 9, 2020 - Meta-analytic approach for transcriptome profiling of herpes simplex virus type 1.
June 13, 2020 - Study: 'In this review, I have briefly described some of the models available and then more thoroughly describe the guinea pig model of acute and recurrent genital herpes infections. As discussed, the guinea pig model most closely mimics human disease and provides several important endpoints for evaluating vaccines and antivirals.'
March 3, 2020 - Tissue-resident T cell-derived cytokines eliminate herpes simplex virus-2–infected cells.
May 22, 2020 - Study: Assess the properties and efficacy of an R2 vaccine derived from the alpha-herpesvirus, pseudorabies virus (PRV), in pigs. We demonstrate that the PRV R2 vaccine does not invade the porcine peripheral nervous system within detection limits. Furthermore, after a single intranasal vaccination, R2 conferred protection to pigs subsequently challenged with a virulent PRV field strain (NIA-3). These findings support that the R2 vaccine design is non-neuroinvasive and is an effective vaccine in the context of a natural host.
May 19, 2020 - Genocea Biosciences, Inc. announced it has entered into a material transfer agreement and exclusive license option with Shionogi & Co., Ltd. to develop a novel HSV-2 vaccine using Genocea’s proprietary HSV-2 antigens from the GEN-003 program.
May 7, 2020 - This model recapitulates clinical responses to natural infection and the rgD-2 vaccine trial outcomes and suggests that ΔgD-2 may prove protective in HSV-1-seropositive hosts.
May 6, 2020 - Newly published research is the first to show in a lab model that the herpes simplex virus HSV-1 might cause Alzheimer's. In the study, scientists found that mini 3D models of the human brain, when infected with the virus that causes cold sores, developed hallmarks of Alzheimer's, including amyloid plaque-like formations and neuroinflammation.
May 1, 2020 - The WHO issued a statement saying, 'About half a billion people worldwide live with genital herpes. Several billion have an oral herpes infection, new estimates show, highlighting the need to improve awareness and scale-up services to prevent and treat herpes.'
March 17, 2020 - Lessons learned from prior vaccine studies and select candidate vaccines are discussed, including a trivalent nucleoside-modified mRNA vaccine that our laboratory is pursuing.
March 2, 2020 - WSU researchers recently published a study in the American Society for Microbiology’s journal mSphere that is the first to identify how one of the virus’ proteins acts as a critical signaler for the virus to succeed in infecting a cell.
April 27, 2020 - Study: Based on our revised annotation of 201 viral transcripts and 284 ORFs, we extended the existing nomenclature to include all our novel viral gene products. This did not involve any renaming of previously described viral gene products. Our terminology thereby explains the gene expression of most viral ORFs in the context of different transcript isoforms, uORF, and uoORFs. This will facilitate functional studies on the viral gene products and their transcriptional and translational regulation.
February 11, 2020 - Study: Current Antivirals and Novel Botanical Molecules Interfering With Herpes Simplex Virus Infection.
February 6, 2020 - Study: Intramuscular vaccination of mice with the human herpes simplex virus type-1(HSV-1) VC2 vaccine, but not its parental strain HSV-1 (F), confers complete protection against lethal ocular HSV-1 (McKrae) pathogenesis.
January 10, 2020 - Sanofi announced Phase 1 and 2 studies were posted. The study's primary objectives are: To describe the safety profile of different investigational vaccine regimens against herpes simplex virus type 2 (HSV-2).To evaluate the efficacy of the investigational vaccine regimens concerning the frequency of herpes simplex virus (HSV) deoxyribonucleic acid (DNA) detection in the genital area (shedding rate) following a 2 dose vaccine schedule; the proportion of participants free of HSV genital recurrence at 6 months after the 2-dose vaccine schedule.
January 8, 2020 - Candel Therapeutics announced the acquisition consolidates a next-generation herpes drug development platform and manufacturing expertise that can tailor to multiple tumor types and indications.
December 17, 2019 - Immune responses to an HSV-2 polynucleotide immunotherapy COR-1 in HSV-2 positive subjects: A randomized double-blinded phase I/IIa trial. This study confirms the previously demonstrated safety of COR-1 in humans and indicates a potential for the use of COR-1 as a therapy to reduce viral shedding in HSV-2 infected subjects.
December 10, 2019 - A recent study provides new insights into the early stages of a Herpes Simplex Virus 1 (HSV-1) infection. It serves as a general blueprint for investigating heterogeneous cell states in virus infection.
December 5, 2019 - A recent study said ‘a significant burden of Human Immunodeficiency Virus (HIV) is likely attributable to a Herpes Simplex Virus type 2 (HSV-2) infection.
November 21, 2019 - Cornell University researchers hoping to learn what switches this life-long virus between latent and lytic stages may have found the ‘hidden’ answer to this question.
November 18, 2019 - Global and regional estimates of the contribution of herpes simplex virus type 2 infection to HIV incidence: a population attributable fraction analysis using published epidemiological data. A significant burden of HIV is likely to be attributable to HSV-2 infection, even if the effect of HSV-2 infection on HIV had been imperfectly measured in studies providing adjusted RR estimates, potentially because of residual confounding. The contribution is likely to be most significant in areas where HSV-2 is highly prevalent, particularly in Africa. New preventive interventions against HSV-2 infection could not only improve the quality of life of millions of people by reducing the prevalence of herpetic genital ulcer disease but could also have an additional, indirect effect on HIV transmission.
September 20, 2019 - A new herpes simplex 2 virus vaccine study in animals reported an experimental vaccine developed at the University of Pennsylvania had prevented genital lesions in 98 percent of mice and guinea pigs tested. Friedman and colleagues just published a paper in Science Immunology in which they describe the trivalent herpes vaccine that they developed and its efficacy in animal models. This trivalent vaccine protected mice and guinea pigs from developing genital lesions and reduced viral shedding. Neutralizing antibody and CD4+ T cell responses were detected in immunized mice.
July 23, 2019 – A patent was issued on February 19, 2019, which protects the use of BlueWillow Biologics’ unique NanoVax adjuvant platform to develop a vaccine that protects against HSV-1 and HSV-2.
July 23, 2019 - X-Vax Technology, Inc. announced that it had raised $56 million in an upsized Series A financing with participation from strategic and institutional investors, including Johnson & Johnson Innovation – JJDC, Inc. Proceeds from the financing will be used to advance X-VAX's lead program, a vaccine candidate against herpes, called ∆gD-2 (delta gD-2), for further development and production, including a Phase 1 clinical study.
June 15, 2019 – A new study published in Nature on June 12, 2019, by Yale researchers offered insights that could lead to a better genital herpes therapeutic vaccine.
May 2, 2019 - Numerous epidemiological, clinical, and immunological studies demonstrate that BCG vaccination impacts subsequent infections' immune response resulting in reduced morbidity and mortality. Important lines of evidence indicating that BCG protects against viral pathogens come from experimental studies in mice showing that BCG offers protection against various DNA and RNA viruses, including herpes and influenza viruses. Recently, BCG's effect on an experimental viral infection in humans has been demonstrated. These effects are thought to be mediated via the induction of innate immune memory and heterologous lymphocyte activation, resulting in enhanced cytokine production, macrophage activity, T-cell responses, and antibody titers.
April 17, 2019 - Therapeutic Mucosal Vaccination of Herpes Simplex Virus 2-Infected Guinea Pigs with Ribonucleotide Reductase 2 (RR2) Protein Boosts Antiviral Neutralizing Antibodies and Local Tissue-Resident CD4+ and CD8+ TRM Cells Associated with Protection against Recurrent Genital Herpes.
March 27, 2019 - Research article: Duration of protection from live attenuated vs. sub unit HSV-2 vaccines in the guinea pig model of genital herpes: Reassessing efficacy using endpoints from clinical trials.
January 22, 2019 - Study: Vaccine-induced antibodies target sequestered viral antigens to prevent ocular HSV-1 pathogenesis, preserve vision, and preempt productive neuronal infection.
November 22, 2018 - Study: The live attenuated prophylactic HSV vaccine, VC2, was effective in the guinea pig model of genital HSV-2. Its decreased ability to infect neural tissues provides advantages over other live attenuated vaccines. The live attenuated prophylactic HSV vaccine, VC2, was effective in the guinea pig model of genital HSV-2. Its decreased ability to infect neural tissues provides advantages over other live attenuated vaccines.
August 11, 2018 - Herpes simplex virus‐2 dynamics as a probe to measure the extremely rapid and spatially localized tissue‐resident T‐cell response.
October 28, 2015 - Global and Regional Estimates of Prevalent and Incident Herpes Simplex Virus Type 1 Infections in 2012.
October 6, 2015 - Original Research: Cost-Effectiveness of Herpes Zoster Vaccine for Persons Aged 50 Years.
January 9, 2014 - Review: The challenge of developing herpes simplex virus 2 vaccines.
January 5, 2012 - The NEJM published an original article: Efficacy Results of a Trial of a Herpes Simplex Vaccine. In a study population representing HSV-1– and HSV-2–seronegative women's general population, the investigational vaccine effectively prevented HSV-1 genital disease and infection but not in preventing HSV-2 disease or infection.
Russian Herpes Vaccine
Vitagerpavac is the only multivalent vaccine globally for treating chronic herpesvirus infection (HCV) of types I and II. The vaccine was developed at the Research Institute of Virology. DI. Ivanovsky RAMS has been used in the Russian Federation for over 15 years.
According to the U.S. CDC, the spread of HSV- 1 generally occurs by direct contact, usually involving saliva, and most commonly appears as cold sores in or around the mouth. And HSV-2 infections usually occur after sexual contact, leading to recurring, often painful, genital sores in up to a third of people infected. And there is no cure for herpes.
On July 16, 2020, new research published in the journal BMJ Global Health found fewer people are being exposed to herpes simplex type 1 – also known as oral herpes – in their childhood. The prevalence amongst the population in Europe is falling by 1% per year. The results also showed that half of the first-episode genital herpes cases in Europe were already due to HSV-1 instead of HSV-2 infection.
About 13% of the world’s population aged 15 to 49 years were living with herpes simplex virus type 2 infection in 2016, the latest year for which data is available. In 2016, two-thirds of the world's population under 50 — about 3.7 billion people — had herpes simplex virus type 1, which most commonly appears as cold sores in or around the mouth, reported the WHO.
Genital herpes infections play a significant role in spreading HIV globally, WHO researchers said.
If a vaccine program for HSV were implemented today and the vaccine was 100% efficacious and utilized by 100% of the target population, the annualized present value of the QALYs gained would be 28,000, says the NIH.
Using committee assumptions of less-than-ideal efficacy and utilization and including time and monetary costs until a vaccine program is implemented, the annualized present value of the QALYs gained would be 7,500.
Most of the disease burden is associated with genital and CNS infections due to the large number of genital infections and the profound, chronic sequelae associated with the relatively fewer CNS HSV disease cases.
The NIH estimates that there are 500,000 new oral infections with HSV each year in the United States. These infections occur in people between 1 and 44 years of age. There are approximately 20,000 new ocular infections with HSV each year. These occur in people between 1 and 84 years of age.
There are approximately 1,500 cases of central nervous system infection with HSV each year. The incidence was assumed to be highest in children between 5 and 14 years of age. It was also believed that there are 300,000 new cases of genital HSV infections occurring primarily in people between 15 and 34 years of age.
There are also 1,500 new cases of neonatal HSV infections each year, says the CDC.
Specific antiviral drugs, including acyclovir and valaciclovir, can control outbreaks, but they don’t cure a herpes infection, says the CDC.
Herpes and HIV
People with HSV-2 infection are at least three times more likely to become infected with HIV if exposed. Thus, HSV-2 likely plays a substantial role in spreading HIV globally. Women are more susceptible to both HSV-2 and HIV.
Women living in the WHO Africa Region have the highest HSV-2 prevalence and exposure to HIV – putting them at the most significant risk of HIV infection.
Interventions targeting HSV-2, such as new HSV vaccines, have the potential for additional benefit against HIV, which could be particularly powerful in regions with a high incidence of co-infection.
Herpes Antiviral Treatments
Most herpes simplex virus infections are self-limited, and treatment is not always indicated or necessary. However, antiviral therapy shortens the symptoms and may prevent dissemination and transmission.
Antiviral medications, such as acyclovir, famciclovir, and valacyclovir, can reduce the severity and frequency of symptoms but cannot cure the infection. About 500 million people worldwide live with genital herpes, and several billion have an oral herpes infection, said the WHO on May 1, 2020.
Treatment of herpes labialis and herpes genitalis generally consists of episodic courses of oral acyclovir, valacyclovir, and ganciclovir. Complicated HSV infections, cutaneous and/or visceral dissemination, neonatal HSV infection, and severe infections in those who are immunocompromised should be treated promptly with intravenous acyclovir, says the CDC.
Patients who are immunocompromised and have recurrent HSV infections, acyclovir-resistant HSV strains have been identified, and treatment with intravenous foscarnet or cidofovir may be used.
Content sources: The WHO, US CDC, WHO, NIH, research papers, ClinicalTrials.gov, and the Precision Vaccinations news network. Content is fact-checked by healthcare providers, such as Dr. Robert Carlson.